16 December 2012

Terrain Wreck

By WarHamSandwich

So I left you last week with a cliffhanger, namely how much does terrain impact your odds of reaching assault?  More specifically:

Is Barra the Berzerker better off charging guardsmen in the open 8” away, or going for a squad in terrain 6” away? What about with rerolls, or with Fleet?

When terrain comes into play, the assault range mechanic gets a little more complicated.  Instead of a straight 2d6 roll, it becomes 3d6 drop the highest.  To show the difference this makes, here’s a straight up comparison:

OpenVsTerrain

So the red line shows the probability of achieving an assault distance in the open, and the green shows the same for terrain.  Unsurprisingly, terrain always makes it harder to reach your opponent, but what’s more important is by how much.  I’ve highlighted two points here as they give us the answer to part of the question I posed.  At 8” the berserker has a 42% chance of reaching the guardsmen in the open, but at 6” he has a 48% chance of reaching the guard in terrain.  The guardsmen in terrain are the right choice of target.

But what about rerolls for the Icon of Wrath?  How does Fleet affect it?

AssaultAll

The chart may seem daunting at first, but hopefully a quick bit of explanation will make it more accessible.  The three red lines are the odds of assaulting a certain distance in the open with no reroll, with a reroll, and with Fleet.  The three green lines are the same but for assaults through terrain.  To address our specific question about 8” in the open vs 6” in cover I’ve again added the relevant dots with percentages.  These clearly show that in a ‘like for like’ comparison (i.e. with a reroll, with fleet) it’s always better to assault 6” in terrain than 8” in the open.  So to answer the original question, Barra the Berzerker should go for the guardsmen in cover in all of our scenarios.

That said, I didn’t build the chart just for this one scenario, you can use it to compare all kinds of situations – and can draw some interesting insights from examining it.

For example, comparing the darkest red line with the darkest green line, we can see that a unit with Fleet charging through terrain has equal or better odds of making assault than a normal unit charging the same distance in the open.

Similarly, checking out the mid-tone green line versus the dark red shows us that when assaulting though terrain units that can reroll charge distance (not Fleet) are also better than normal units charging in the open but only for distances up to 6”.  After this point we see a crossover in the lines and a normal charging in the open is better from 7” onward.

Even simply taking a look at the normal line, vs the reroll line, vs the Fleet line can really highlight how big a difference these abilities can make.

I do have to apply the caveat that my analysis assumes that the player using Fleet always makes the optimal choice for which dice to reroll.  But you’ll have to wait for those rules until next week…

1 Comment   |  tags: , , , , | posted in Probability

12 December 2012

A Pinch of Assault

By WarHamSandwich

Assault ranges were one of the biggest changes in the move to 6th edition.  In total opposition to 5th ed, we gained the right to premeasure the charge range, but lost the ability to know exactly how far we could charge.  I’m sure Heisenberg would be proud… So here’s a question for you:

Barra the Berzerker Champion is leading his unit to collect more skulls for the brass throne of mighty Khorne.  8” to his left in open terrain is a squad guardsmen, 6” to his right is another guard squad in cover – which is he more likely to reach?  If he had a banner of wrath how would that affect his chances, and what if it had been a unit of Possessed rather than of Berzerkers?

For most units in 6th ed, the charge range is determined by the sum of 2d6, or if in terrain, 3d6 dropping the highest.  The mechanics get more complicated as some units can get a reroll, and others can reroll specific dice (i.e. Fleet).  As most of you know, 7 is the average result on 2d6, but this can lead to the unfortunate assumption that you should expect at least a 7.  I’m sure as more people get some games in and launch assaults in 6th, they realise that this is not the case…

Let’s look at the no terrain mechanic first.  I’ve charted the odds of making the charge for a straight 2d6, 2d6 with a reroll, and Fleet (i.e. reroll either or both dice). AssaultOddsOpen

Unsurprisingly, having a reroll improves your chances, and being able to pick and choose which die to reroll increases your odds even further.  That assumes you know when is the best time to reroll just one dice (i.e. my results assume you make the optimal choice in all instances).

We can see from the chart that at 8″ our Berzerker friend has only a 42% chance of reaching the guardsmen in open terrain.  If his squad has the Icon of Wrath, then he can reroll charge distances, which would bump his odds of reaching them to 66%.  A Possessed Chaos Marine has Fleet, which enables him to pick and choose which dice to reroll – raising the odds of reaching those guardsmen to 72%.

To make life easier for you dear reader, for units with fleet, I’ve got some rules to make sure you make the best reroll you can:

Range: 3” or 4” reroll both

Range: 5” reroll anything ❤

Range: 6” to 10” reroll anything <4

Range: 11” reroll anything <5

Range: 12” reroll anything <6

Note1: when I say reroll anything <x I mean if both dice are <x reroll both, and if one die is <x reroll just that one.

Note2: If the above rules don’t work for a specific result then reroll the lowest die only e.g. range 10” and you roll a 4 and a 5 (say), just reroll the 4.  In the case of doubles, just arbitrarily pick one for the reroll and keep the other.

So what about the terrain?  In the question above the Guardsmen in terrain are closer, but does the terrain make it less likely to reach?  You’ll have to tune in next week for that one my friends!

3 Comments   |  tags: , , , | posted in Probability

29 November 2012

Ireland’s Call

By WarHamSandwich

20121129-141650.jpg

The recruitment campaign now starts in earnest! Prospective 40k players for Ireland’s ETC 2013 team should make themselves known on W-ired or Onthestep

Last year we broke into the top ten, I dare you to do better!

Leave a comment   |  tags: , | posted in ETC

28 November 2012

Dealing with Cron Air

By WarHamSandwich

Flyers in general, and necron flyers in particular, have really got many players worried and/or frustrated.

Nevertheless, a crucial weakness of pure flyer lists is the requirement to have units on the board at the end of every game turn. If the vast majority of the armies points are in flyers that can’t come in until turn 2, then killing the few ground units they have in turn 1 gets you an auto win before a single flyer enters play.

However, wiping even just a handful of units in turn one is not an easy task; especially so if your opponent is hiding them well. So far, some Daemons lists have excelled at this, since half the army deepstrikes in on turn 1 and can focus in on the enemy’s hiding spots.

What I’ve been pondering, is how an Imperial Guard army might achieve that difficult turn 1 wipeout. I think the key to this is captured in the quote:

Infantry win firefights. Tanks win battles. Artillery win wars.

The plethora of excellent artillery choices lets you drop devastating pie plates from afar, and even on units that you can’t see – thanks to indirect fire.

The inclusion of Gunnery Sergeant Harker lets you infiltrate a veteran squad, which can be placed with the right firepower to mop up the remains of a unit post-bombardment.

In case it doesn’t go to plan, I’ve included 3 vendettas to take on flyers that do make it in to play, and a Master of the Fleet to slow down the rate at which those flyers come into play.

So here’s the list:

HQ – 80
Company Command Squad (80)
Company Commander; Master of the Fleet.

Troops – 445
Veteran Squad (150)
Gunnery Sergeant Harker; 3× grenade launcher; Veteran Weapons Team (heavy bolter).

Platoon Command Squad (295)
Platoon Commander; Heavy Weapons Team (autocannon).
• Infantry Squad: +1 Sergeant.
• Infantry Squad: +1 Sergeant; krak grenades.
• Heavy Weapon Squad: 3× autocannon.
• Heavy Weapon Squad: 3× autocannon.

Fast Attack – 420
1 Vendetta Gunship (140)
sponson heavy bolters.

1 Vendetta Gunship (140)
sponson heavy bolters.

1 Vendetta Gunship (140)
sponson heavy bolters.

Heavy Support – 805
1 Ordnance Battery (420)
• Colossus
• Colossus
• Colossus

Manticore Rocket Launcher (160)

1 Ordnance Battery (225)
• Griffon
• Griffon
• Griffon

Detachment: Fortifications

Other – 100
Aegis Defence Lines (100)
Quad Gun.

1,850 points

As an added bonus, I think it will scare horde infantry lists; which are also gaining popularity in the tournament scene.

3 Comments   |  tags: , , , | posted in ETC, Tactics and Techniques, Tournament

3 November 2012

Krak vs Frag

By WarHamSandwich

One ‘fast call’ that often crops up is the decision of Krak vs Frag missiles when targeting MEQs. So here’s a question:

Devastator, Long Fang, Space Marines, Space Wolves

Lothar the Longfang stands atop a bastion with clear sight to a squad of chaos marines. He sees one in the open, with four comrades in cover. Should he use a krak on the one, or frag on the four? What if all 5 were in cover?

Chaos Marines

6th edition has introduced the concept of focus fire, whereby you can pick out individual models in the open, and has also reduced some of the standard sources of cover save (e.g. area terrain, and firing through enemy units). Both these changes affect the decision to go frag or krak vs armored targets.

Let’s take the simple stuff first, say Lothar fires a krak at the marine in the open – how does that pan out. With 3’s to hit, and 2’s to wound theres a 56% chance of killing the marine. What about the frag on the four? Well the scatter die is generally worse than all but the lowest BS values, so Lothar’s odds of hitting will likely drop (though this is quite dependent on the layout of the target models and any other nearby models that could be hit by a scatter). My previous analysis, puts BS4 scatter as about equivalent to BS3, so lets say 4+ to hit, 4+ to wound, and 3+ armor saves; and let’s say one blast marker can cover all four targets. This gets us an expected kill rate of less than 37% – worse than the krak. In fact, you’d need to cover about 7 marines before it was as effective as 1 krak shot (with no cover).

Of course, opponents are not always so obliging, and all your targets may be in cover. With 5+ cover that Krak missile drops to a 37% chance of a kill, and 4+ cover drops it to 28%. So how does the frag compare in these circumstances? A frag blast that covers 3 marines is roughly equivalent to 1 krak into 4+ cover. In 5+ cover you need about 5 marines covered to be worth your while.

So what’s the answer to our question? Well, with some dope in the open, Lothar should krak away rather than frag the four. But when it’s five in (say 5+) cover then it edges towards frag – but there’s something you should keep in mind:

They are roughly equivalent but there’s a key difference here – I’m using the ‘expected’ number of wounds to compare, but a krak can only kill 1 marine whereas the frag can kill multiple. The catch is: while the frag can kill more, your are also more likely to walk away with no kills at all. The concept here is volatility – if you need that one kill then the krak is more reliable even in situations where the average says they are equivalent. Sometimes though, you need to take the chance on getting multiple kills (e.g. to force a break test) and for that you need the frag.

1 Comment   |  tags: , , , , | posted in Probability

28 October 2012

Fast Calls

By WarHamSandwich

In the heat of battle you have to make all kinds of on the spot decisions. Sometimes these are judgment calls with no analytically right or wrong answer – you just go with what feels right. However, sometimes even very good players do this in situations where a bit of thought would lead them to a definitively right choice.

For example, during the 2012 ETC, my opponent and I were discussing a cover save for a squad of my chaos marines. I contended that they were in 4+ cover, he said no. After some debate he offered me to ‘4+ it’ to determine if they were in cover, to which I offered a flat 5+ cover save which he accepted. In a later game the same situation arose with a squad of Obliterators, this time I agreed to ‘4+ it’. So here’s a simple question for you:

Was I right to take a different approach to two seemingly identical situations?

In the case of marines, they needed cover to have any save at all, rolling a 4+ to see if they are in cover of 4+ needs two 4+s which is only 25% likely. Arguing for a 5+ got me a 33% survival chance. So heres a rule of thumb, if your opponent offers a 4+ on 4+, offer a flat 5+. If an opponent asks for a 5+ get him to 4+ it instead.

Then why the change for the Obliterators? Well, like all good rules of thumb, you need to know your exceptions. The key difference is that if the Obliterators aren’t in cover, they still have their 5+ invulnerable – arguing 5+ cover would achieve nothing. I should roll for the 4+ to try for 4+ cover and if I’m not in cover then I can still use the invulnerable.

There was a similar situation against Imperial Guard. The IG order “Fire on my target” forces you to reroll successful cover saves. A quick bit of math and I chose the 5+ invulnerable vs 4+ cover, for the same statistical reasoning as before – a 33% chance of survival vs a 25% chance.

Whenever you find yourself in these kinds of situation, take a moment to think about it – because eking out a few extra percentage points can win you a tight game, and aren’t those the best victories?

1 Comment   |  tags: , , , | posted in Probability

22 October 2012

Basic Anti Air

By WarHamSandwich

I realize that it’s been a while since I’ve thrown some numbers at you, and isn’t that really the purpose of this blog? So back on form, here’s a question:

Icarus was the boy of legend who flew too close to the sun, but if he traded his wax wings for a vendetta, then how worried should he be about the skyfire interceptor lascannon that they named after him?

20121022-205713.jpg

Flyers are the new hotness of 6th edition and everyone needs to have a way of dealing with them in order to stay competitive. The BRB gives us two generic options, the Icarus Lascannon, and the Quad Gun.

Both have the very interesting interceptor rule, which lets them take a pot shot at any enemy unit that has arrived from reserve that turn – so you get a chance to blow that flyer out of the sky at the end of his movement phase (before he gets a chance to fire).

Both fire at full BS vs. flyers (thanks to the skyfire rule), and given that flyers are usually medium armour at best, you’d be hopeful of getting a lucky shot in to pop your opponent’s beloved flying machine of death. Unfortunately the numbers aren’t really on your side…

So that Vendetta flies onto the board full of hopes, dreams, and heavy weapons, how does he fare? Let’s take the Icarus Lascannon first.

20121022-205839.jpg

Assuming BS4, with fours to pen his AV12, and fives on the damage chart to explode him we get an 11% chance of success (which drops to 7% if your opponent evades). The hull point view isn’t great either, we can do at most 1 hull point, but the expected value is 0.3 hull points.

20121022-205957.jpg

The quad gun is certainly a better bet for doing hull point damage (not so hot for an explodes result). We can potentially do 4 Hull points of damage to that Vendetta! But what are the odds?

Hull Points inflicted vs Odds
0 41%
1 41%
2 15%
3 2%
4 <1%

As you can see, not great. The expected value is 0.79 Hull Points, which is a lot better than the Icarus, but still not a major threat.

Running a few more numbers, I came across a sad truth. A snap firing twin linked tesla destructor (i.e without skyfire) is as dangerous to a vendetta as the dedicated AA Quad Gun.

So to answer my original question, our vendetta pilot shouldn’t sweat it, but my overall conclusion can be summed up as:

God damn necrons.

1 Comment   |  tags: , , , , | posted in Probability

22 October 2012

Ireland ETC 2013 part 01

By WarHamSandwich

I’ve recently been given the honour of becoming the 2013 captain for Ireland’s 40k team for the ETC. With the outgoing captain, Mike Tangney, having overseen Ireland’s best performance to date, I’ll have some big shoes to fill.

Thankfully I have a pool of excellent players to build the team, and have a small army of volunteers to help with the organisation.

Today’s post is just a snapshot of where the current rankings lie, as these will be a key component of team selection. Heres the latest rankings top 20:

40K (IRE)
Paul Quigley
Dan Ahern
Alec Cornelius
John Stowe
Jonny Fisher
Richard Flood
Ivan Sheehan
Scott Nelson
Eoin O’Mahony
Jan Karnowski
Michael Tangney
Mervyn Murphy
Philip Johnston
Dave Coleman
Peter Scott
Rowan Sheridan
Luke Osbourne
Tom O’Reilly
Brian Leonard
Javier Jimenez

As you can see we’ve got a good mix of former ETC vets and new blood vying for the top slots. Obviously it’s early days yet, and I expect to see lots of changes over the next 5 months, but I’ll post regular updates of the rankings scene and keep track of how people are progressing over the rest of the season.

Leave a comment   |  tags: , | posted in ETC

3 October 2012

IG and me

By WarHamSandwich

I played my first 6th ed tournament, using a combo of chaos marines and imperial guard. The format was escalation from 1000 to 2000 over 5 games with a 250 point uplift from round to round.

I brought a list that tried to include a bit of everything: flyers, deep strikers, flying monster, jump infantry, artillery, fortification etc.

Overall they were decent but definitely suboptimal lists, so I won’t bore you with the breakdown – but I did take the time to reflect on my games and come up with a list that is more evolved.

So 1750 points will get you:
Imperial Guard

HQ
Company Command Squad
Company Commander; Astropath; Master of Ordnance; Master of the Fleet; camo cloaks.

Elites
Guardsman Marbo

Troops
Platoon Command Squad
Platoon Commander.
• Infantry Squad: +1 Sergeant (melta bombs); flamer; krak grenades; Heavy Weapons Team (heavy bolter).
• Infantry Squad: +1 Sergeant (melta bombs); flamer; krak grenades; Heavy Weapons Team (heavy bolter).
• Heavy Weapon Squad: 3× autocannon.

Platoon Command Squad
Platoon Commander.
• Infantry Squad: +1 Sergeant (melta bombs); sniper rifle; krak grenades; Heavy Weapons Team (missile launcher).
• Infantry Squad: +1 Sergeant (melta bombs); sniper rifle; krak grenades; Heavy Weapons Team (missile launcher).
• Special Weapon Squad: 3× demolition charge.

Fast Attack
1 Vendetta Gunship
sponson heavy bolters.

1 Vendetta Gunship
sponson heavy bolters.

1 Vendetta Gunship

Heavy Support
2 Hydra Flak Tanks

Manticore Rocket Launcher
pintle-mounted heavy stubber; camo netting.

2 Hydra Flak Tanks

Fortifications
Aegis Defence Lines
Quad Gun.

Since chaos is in flux right now I’ve left them out of the list That said, with the new chaos codex coming out this week you can expect to see more from me on the IG+CSM combo in the near future.

2 Comments   |  tags: , , | posted in Tactics and Techniques

29 January 2012

Warpcon

By WarHamSandwich

This weekend saw one of Ireland’s biggest 40k tournaments run in Cork. It was my first time attending Warpcon, and coincidentally my first time competing at the new 1850 limit.  Strangely enough, I noticed that Cork airport has a very 40k appropriate three letter IATA Code:

As I mentioned previously I’ve done some head scratching as to how best to bump my 1750 list up to 1850. This time I went with a multimelta armed chaos dreadnought.   So my final list was as follows:

HQ1: Daemon Prince Mark of Slaanesh Wings Lash of Submission [155 Pts]
Elite1: 3 terminators 3x Combi-melta [105 Pts] in Transport 1
Elite2: 3 terminators 3x Combi-plasma [105 Pts] in Transport 2
Elite3: 1 Chaos Dreadnought, with Multimelta [100]
Troop1: 5 chaos marines  [75 Pts]
Troop2: 5 chaos marines  [75 Pts]
Troop3: 5 chaos marines, Icon of Chaos Glory [85 Pts] in Transport 3
Heavy1: 3 Obliterators [225 Pts]
Heavy2: 3 Obliterators [225 Pts]
Heavy3: 3 Obliterators [225 Pts]
Transport1 : Landraider [220 Pts] Carries Elite1
Transport2 : Landraider [220 Pts] Carries Elite2
Transport3 : Rhino [35 Pts] Carries Troop3
[1850pts]

ROUND 1

MISSION Primary Seize Ground, Secondary Capture and Control, Pitched Battle Deployment

My first game was against Mark and his Dark Eldar army.

Mark had a really interesting mixed dark eldar force – Wyches, Raiders, Beasts, Talos, Venom, Ravager, Warriors, Wracks, Hellions, Incubi and more.  A good set of turn two deepstrikes let me do some serious damage to his force, but we were pretty evenly matched until turn 5.  In one turn I managed to contest the two primary objectives he had been holding, and flush him off his home objective while holding one of the primaries and my home.  The very end of the game was pretty epic: it’s looking like a 14-6 to me, after movement I’m about 6″ away from the objective that he’s holding – I roll for a run with the one squad in range, the six comes up and the 14-6 becomes 18-2.  Game ends

RESULT 18-2 WIN

ROUND 2

MISSION Primary Capture and Control, Secondary KillPoints, Spearhead Deployment

Next up was against Dave and his Blood Angels army.

Blood Angels are a fast and dangerous army.  Dave had Death Company, Astaroth and a Libby Dread in a Raven; Assault Terminators in a Redeemer, a Speeder, and two squads (one in a pod, and one in a Rhino).

I had first turn, and set up my Raider and Oblits with good fire lanes across the whole table.  I was able to shoot up all his transports while they were still far away, thus giving me the opportunity to use my firepower against him for the whole game and avoid getting into assaults.  Without mobility, Dave had a tough time of it, but was a great opponent.  The game went the full 7 turns, and I held my objective, had managed to sneak a rhino onto his, and was comfortably ahead on KPs.

RESULT 19-1 WIN

ROUND 3

MISSION Primary KillPoints, Secondary Capture and Control, Dawn of War Deployment

Last game of the day was against Rowan and his Clockwork Necron army.

This was my first game against the new Necrons, and Rowan had heeded my advice and had brought plenty of Tesla.  He had also taken lots of tricksy stuff – so I faced THREE turns of nightfighting, and thanks to Anrakyr the Traveller my own Landraider started shooting my Oblits.  But the really dangerous bit of the list was the wraiths.  They were jumppacking, rending, 2 wound, stormshield carrying death machines.

I killed most of Rowans skimmers but just bounced off those wraiths.  Rowan played really well, and I learned a lot about the sneaky tricks of the new codex. I must say necrons are really interesting, and I’m going to have to do some heavy thinking on how I can best take them on…

Ended the day on a loss – needed to get back into the fight in the morning!

RESULT 5-15 LOSS

ROUND 4

MISSION Primary Seize Ground, Secondary KillPoints, Spearhead Deployment

My first game was against Burkhardt and his incredibly painted Blood Angels army.

Burkhardt had first turn, and deployed his whole army (bar his sanguinary guard and honour guard) on the left flank.  As with all BA opponents, I needed to keep him away and get some solid shooting in before any of his units reached my lines.  So I deployed a refuse flank, with just my 2 landraiders and one squad of obliterators in the far right corner.  Off to a good start.

Turn 1 his two lascannons manage to immobilise and stun one raider, and I have to go to ground for my oblit squad to weather the hail of bloodstrike missiles.  So turn one I have just one raider to shoot back with, and he fails to scratch the raven.

Turn 2 his honour guard (with melta guns), and sang guard (with inferno pistols) DoA next to the undamaged raider, but not close enough for 2d6 pen.  Not that that mattered since he glanced it and rolled a 6, with the AP1 bumping that up to Destroyed Wrecked.  😦 My turn 2 my melta terminators roll a 10 for scatter and mishap (these things happen).  My oblits drop down with clear LOS to his honour guard, and roll an 11 for scatter putting them 0.5 inches off the table. 😦   On the plus side my remaining 6 oblits down his raven which had boosted towards my lines.  In a true combined arms fashion, my plasma terminators did manage to mess up the terminators that popped out of the raven, but didn’t manage to finish off the unit.  Unfortunately his blood talon dread was eyeing them up with glee…

Turn 3 his sang guard assault my oblits, whittling them down.  His honour guard just hang about having fluffed their difficult terrain.  His lasback and autolas pred popped the remaining oblit squad – three shots, three kills.  😦   As expected, the blood talon dread devoured the terminators.  My turn 3,  I move up my marines towards objectives, and make a really stupid mistake: I forgot to shoot with my immobilised Land Raider.   The daemon prince takes on the honour guard (and fails to kill anything!).  😦   The chaos dread rushes in and assaults the sang guard but does no damage, but he’ll grind them down – right?

Turn 4 he blows up my last Land Raider with his autolas pred, and his two razorbacks take up objective holding positions.  His Blood Talon Dread jumps into the Daemon Prince combat, but luckily I chop him down before he gets a chance to strike and   My turn 4  my Dread finishes off the last Sang Guard but the sang guard have popped the last oblit.

Turn 5 he bolts forward with his death company towards my right flank objective.  He holds two, I hold one, and the right flank is contested.  My turn 5 the dread lumbers towards the death company, but with only a two for difficult terrain meant I wasn’t able to close the gap.  So I piled him in to the daemon prince/honour guard fight and wiped his squad.  Now I need another turn to claw back that draw! Game ends

😦

RESULT 3-17 LOSS

ROUND 5

MISSION Primary KillPoints, Secondary Seize Ground, Pitched Battle Deployment

My last game was against Loyd and his Dark Angel army.

Loyd’s army was exactly the mix of light mech and walking marines that my list excels against, and after my harrowing loss in the last round I was looking for blood.  I seize the initiative, and do some damage to his tanks.  Lash + plasma terminators + oblits whittle down his assault squad and Belial’s squad.  Meltacides kill his dreadnought and mop up two of his scoring units in assault.  Land raiders tear up his vehicles.  By turn 5 he has two models left – one more turn needed to get the 20-0!  But game ends

RESULT 18-2 WIN

Leave a comment   |  tags: , , , , | posted in Tournament

%d bloggers like this: