Greeting, fellow hard-boiled New York City detectives! Today I bring you a bit of mathammer. No, don’t worry, I’m not going to rant about Tactical Squads again… Though Tactical Squad users may get some mileage out of the info I will present here, given it concerns what is probably the best weapon to give to a Tactical Squad Sergeant: the Combi-Plasma.

As a bit of background, I’m working on a new tournament list that will feature Lias Issodon and a bunch of Sternguards equipped with Combi-Plasmas. In order to make sure I was getting the most out of these expensive dudes, I went through the trouble of running a comparison between using only the plasma part of the gun and when using the plasma AND the boltgun with the penalty to hit. What follows are the results.

A caveat: I came in with the assumption that I wouldn’t be overcharging the Plasma when I’m firing both it and the bolter because the to-hit penalty makes that a pretty suicidal proposition. Even with rerolls to hit, you’re looking at an 11% chance of nuking yourself, and that’s outside of rapid-fire range…

I also assumed that I’d generally avoid overcharging the Plasma against single wound models. Against T4 models, you get a bit more reliability with your to-wound rolls, but in most circumstances, the possibility of dying is probably not going to be worth it.

Finally, I didn’t factor in additional to-hit modifiers (like Alaitoc/Alpha Legion/Raven Guard traits) because I’m fairly certain it was going to be too much for the Bolter & Plasma to overcome (so always use only the Plasma part when you have negative to-hit mods).

The Charts

I’ve peppered this post with charts that depict the results of my calculations. They are pretty self-explanatory: profiles of a potential target across the top (Toughness, Armour and/or Invul Save and sometime Wounds), weapon profile used (Plasma part of the combi only, overcharged Plasma only or both the Plasma and Bolter parts of the combi) and finally, the average amount of wounds caused, with the numbers in the green background being the highest of the two for easy visual reference.

Shooting at Multi-Wound Models

Getting the obvious out of the way: you’re better off shooting only the overcharged Plasma against multi-wound (MW) models than shooting the non-overcharged Plasma and the Bolter. In the table below, I compared two of the weakest MW models I could think of to see if there was a glimmer of a chance that the overcharged Plasma wouldn’t be flat out the best against every MW model in the game. Nope!

Even against Nurglings and Ripper Swarms, shooting the overcharged Plasma is better. In fact, I didn’t even take into account the fact that shooting 1D weapons at the Nurglings would force some Disgusting Resilience rolls.

Shooting at Single-Wound Models without an Invulnerable Save

Here there are actually things you are better off using the Bolter & Plasma parts against:

So against T3 targets, you are always better off using both the Plasma and Bolter unless the target has a 2+ Armour Save… I’m not even sure there are any such models in the game right now. EDIT: As was pointed out in the comments, Sisters of Battle in cover would get what is basically a 2+ save.

Against T4 models, you should use the Plasma only against 3+ saves and better, and both Plasma and Bolter against all others.

I didn’t look at T2 and below or T5 and above targets because – if I am not mistaken – there are no single-wound models with that profile.

Shooting at Single-Wound Models WITH an Invulnerable Save

This is where shooting both weapons really shines:

As you see, there are a few cases (some of which I’m not even sure exist, again) where shooting just the Plasma is better, but they are few and far between, so as a general rule, you should always use both the Plasma and Bolter against single-wound models with an invul.

Summary & Conclusion

So to summarise and generalise my findings into some easily remembered (if not 100% accurate) rules:

Against multi-wound models, always use the overcharged Plasma only.

Against single-wound models with an invulnerable save of any kind, always use both Plasma and Bolter.

Against single-wound T3 models without an invul, always use both Plasma and Bolter.

Against MEQ (T4 3+) models and better, use only the Plasma; use both Plasma and Bolter against all other single-wound T4 models without an invul.

And there you have it! I realise this article is extremely narrow in focus but I had done the math already so I figured I may as well share it.

Cheers!