Wednesday, October 12, 2011

How many Missiles to the Center of a Razorback?

So for fun, I wrote up a little Monte Carlo generator for determining the probability of destroying vehicles based on all the relevant parameters. While it is trivial to calculate whether a single shot will destroy a vehicle, if you want to do it properly you have to worry about the things like multiple weapon destroyed results leading to destruction and that all member of a unit fire at once. Instead of going through and trying to rigorously calculate the results, you just simulate the process a hundred thousand times. So the question I asked is how many times does the unit have to shoot at the target to get a destroyed result. The results are shown as a cumulative probability so you know that for example if you shoot at the vehicle 5 times it has some probability of being destroyed. It could have been the first shot or the last shot.

So the first thing we will look at is the difference between a standard 1 weapon razorback and las-plas razorback which 2 weapons adds to its damage capacity.

This plot pretty much shows the one of the problems with 40K right now. Here you have a elite warrior with line of sight and weapon in range with an anti tank weapon firing on an APC not a main battle tank. You do not reach 80% probability of destroying the Razorback until 10 missile shots. You can see that the extra weapon buys you 1 more missile shots on average before being destroyed. The mean number of shots to kill the razorback is 7.3 missile. This helps to illustrate the weakness of a unit like the tactical squad in this meta. You spend 170 points and get a heavy weapon that will not even on average kill a 50 point tank in an entire game. So in an army with 12 razorbacks you will need 87 missile shots to kill all those transports on average. Now 6 tactical squads are not going to bring that much firepower in 12 turns so you need devastators but things get a little worse since they fire missiles in groups of 4.

Now lets compare what a 4 Missile Launcher devastator unit does against razorbacks compared to the Rifleman Dreadnought.

With 4 missiles at a time you get destruction at 80% of the time after 3 sets of shots but this means 2 more missiles used than with the individual shots. The mean in 2.24 turns of shooting. Now if you have 12 razorbacks to kill it will require 27 turns of devastator shooting. This is 50% higher than your 3 devastator squads can deliver in the 6 turn games assuming that they take no damage (which is not going to happen since 12 HB psibacks kills 9 marines a turn). So their 600 points kills 160 points a turn and your 700 points (you are going to want some spare marines if you expect to have any missiles left after the first turn) kills 50 points a turn.

The Rifleman dread under performs the devastators where it takes him 4 turns to get the 80% point on the razorback. Add in Psibolts and he does better due to the twin linking.

What do you guys think? Are the light vehicles to tough. Should these tanks really survive 8 missiles shot by the emperors finest.


  1. Very interesting analysis, really shows how having a heavy weapon in a tactical squad (or similar squad) is more for the psychological edge than anything else.

  2. This is why lances fail ...I just spent a 'wonderful' evening more or less failing to penetrate anything with my 20 + lance weps, sadly its my only AT, what little did go through was often glances got reduced to 1's and 2's which was promptly ignored by my GK opponent,

    $ turns inot the game I had killed a single psyfleman dread , his other five vehicles were untouched, I phsically could not roll high consistently enough to do anything, sadly your stats just back up the IRL results.

    sadface :o(

  3. I think the biggest problem with 40K these days is math-hammer. The mere fact that its now the norm to see people plotting probabilities makes me shudder. NO offense to you or this post, it was well done and on the face of it I don't disagree at all. I just miss the days when people rolled dice and focused on a fun social game and some good ole BSing about the awesome GW universe. Those days are long gone and 40K has gone the way of collectible games as far as the competitive side of 40K.

  4. Sorrowshard- Lances at least keep some semblance of use against heavy armor. I am going to look at that in a day or 2.

    Lord- My goal here is really to follow up on my post about the game being broken where armies can field 12 vehicles each one fielding more effective firepower than a tac squad. I do the math hammer not to optimize my list but more to understand the state of the rules and because I am a nerd who like math. Plus I needed to practice some programming to fresh my memory on the language.

    While I do not go to many events seeing the list people bring just makes me shudder. A casual player more of army collector like me just is up a creek against these lists. I think our community is to small to fracture between people who want to kick in teeth and people who just want to move a few plastic guys around the table. I would not expect to win many games in the current meta but I think I would just get destroyed.

  5. Now do the math on how survivable a Mycetic Spore is (about the same points)! I'm sure that we will see that the problem with 5th edition is that vehicles are WAYYYYY too survivable/cheap.

  6. Mycetic Spore is a bad comparison since it is only toughness 4 so can be instant deathed with a missile. A single missile has a 55 percent chance of killing. 2 get to the 80% level and the mean number is 1.8 so about 4 times easier to kill than a rhino or razorback.

  7. I would love a lance evaluation, any way you can make cost a factor , I think they may even be demonstrably worse than ML's against the majority of armor targets with cost as a factor.

  8. Just points out how light vehicles are too hard to kill, or are undercosted.
    Its unfair to say they are just too hard to kill, since a 35/50 point rhino is AV11 while many other races pay through the nose for AV12 or even the same AV 11 (or 10).

    If you weaken vehicles then sure footslogging and weapons become more viable, and armies like Eldar, DE, Tau etc all end up totally screwed as well because they pay big points for their vehicles unlike Space Marines and Guard.

    The real issue here is that cheap vehicles that sell for the same price as a squad of models, but are 1/3 the actual ingame points if not even less is a marketing ploy to make money.
    Marketing being a factor in game design = major fail when it skews the gaming system like this.

    Drop the price of most non guard/SM vehicles by 30-40% and you'll have evened the playing field. Or in reality made SM players feel the pain, and since apparently only their whining matters things will be changed.

  9. @erichrome:

    Sure lances beat ML against everything with av13-14. But as you said youself: if someone starts spamming chimeras+vets or something close to a double-digit of razorbacks, having a lance rule on your weapon helps you nothing. Heck, it just blows the costs for your weapons out of the window. A DE Blaster is worse than a melta in 9 out of 10 cases and that even w/o factoring the possible 2d6 into the equation. Is having 6" more range really worth not having ap1 and paying an extra of +5 points?

    Regarding light vehicles in general: I think the big problem isn't really the price alone that you pay for most transports (ironically the only transport that got a point increase in ed5 was the raider..go figure). It's the increased durability the whole packet gets compared to both dedicated battle tanks and footslogging infantry. Esp. when it comes to ensuring the firepower of the packet.

    Depending on how many wounds you create and/or the ratio of heavy weapon guys vs bullet catchers, the AT capability of a infantry unit can be either killed of in one turn, degrades with each ongoing turn or stays the same until you kill every single guy. If you plaster a squad of longfangs with venoms, they may die in a single turn. If not their firepower will decrease with each following turn. You can manage to inflict enough wounds on a split up tac squad to kill the dude with the ML thanks to the "torrent of fire" rule. Or you may end up killing each bolter guys until the guy with the ML dies at last. In any case you need to kill them to keep them from bringing their AT-capacity into play.

    A dedicated battletank can be either denied one turn of shooting thanks to a simple stun/shaken result. Or if its one of those single weapon tanks like a vindicator or prism tank, one "weapon destroyed result" also does the trick.

    A cheap transport with embarked AT capability? As long as it can move, it will deliver the cargo and any shaken result will mean squat for the infantry squad after it disembarks.

    So while you can kill a single ML from a tac squad through torrent of fire or ignore a enemy battle tank after a single stun/shaken result, that won't work with a chimera filled with melta vets.

  10. In terms of the non marine vehicles, the issue is more that extra point of armor does not buy you very much in extra survivability. I think most vehicles when moving flat over 6 inches should probably get a 5+ cover save while flat out skimmers a 3+. Fast vehicles then would pick up some additional survivability while still having some firepower output. A Raider moving flat out should be tough to hit but if you do hit it should probably go down. They should be especially vulnerable when loading and unloading.

  11. Flat out or fast moving raider as an alternative to keeping the troop section cheap with min-sized wrack squads inside venoms only works if the rules for embarked passengers change.

    Right now there is no reason to field 10guys strong Warrior squads with raiders. If transport skimmers need the movement to balance out their worse chances for cover saves from terrain/LOS and keep infantry from hitting them too easily at their back armor, they must either have a big price increase or some changes in the rules for fast open topped transports/skimmers. Since we won't see a new DE dex in the near future (say ed6 or early ed7) and GW doesn't fix units via erratas like PP does, this means the only chance to make raiders work compared to stuff like 35pt rhinos or 55point chimeras is to make those change on a general basis with the ed6 rule book.

    At least that's my personal opinion. I mean the whole DE background in the codex tells you that warriors favor fly by attacks, strafing the hell out of their targets because they neither have the money for a proper haemonculi "life insurance", nor are crazy enough (like wyches) to wage a close combat fight against anything that hasn't been reduced down to a number that massively favors the warriors.

    So the fluff ideal for a warrior squad on a table that rides in a raider is to move around, shoot stuff from inside their moving vehicle (thus get the splinter rack bonus) and leave mopping up stuff to wyches, beasts, hellions and incubi. Sadly that doesn't work, because GW nerfed the hell out of skimmers in ed5 by not only dropping the broken "cruise speed=only glances" rule skimmer (which was the right thing to do), but also both dropping the speed limit for embarked passengers and the unique rule for hitting non-immobilized skimmers in cc.

    Not to mention that ravagers would still be as useless as falcons when it comes to mobile fire-power if PK hadn't invented the "aerial assault" special ability. The changes to the defensive weapons was far more brutal on skimmers than on stuff like predators.

  12. I have to say I do not know all the details for the DE stuff since I refuse to buy a codex for every army and my will to play was crushed by the nid release.

    The M42 project(in my blog list) is trying to develop some alternative rules for far future space fantacy so you can check that out

  13. I liked this article a lot. It would be interesting to see the data for meltaguns and lascannons. Maybe those things vs AV14.