So we played a pretty big game last night. 1500 Chaos Marines and 1500 Orks (me) versus 1500 Tyranids and 1500 Marines.
My list:
1 Big mek with big choppa and KFF
25 Ork shoota boyz - nob with power klaw
12 Slugga boyz - nob with power klaw
4 Grot Tanks with 5 rokkits and 5 shootas
1 Morkanaut - KFF
1 Kill Tank - Bursta kannon, twin big shoota, skorcha
1 Dakkajet
1 Burnabomma - burna rokkits
The game as an absolute bloodbath.
My remaining models:
1 Kill tank with 17 wounds remaining
2 Grot tanks
1 Burna Bomma
1 Mek with KFF
The rest of the models still on the table?
My partner:
9 Chaos Marines
3 chaos marines
1 Helldrake
Enemy marine player:
2 Devastators
6 Marines
1 Razorback
1 Chaplain (warlord)
Enemy Tyranid:
Nothing
So what worked and what didn't?
Kill Tank and Moranaut made for a brutal combination. Two T8 high wound models was VERY hard to handle. The enemy had to leave one entirely alone so they could try to stop the other. It took three turns of continuous fire to bring down the morkanaut. A total of 18 lascannon shots, 38 assault cannon shots, and countless devourer and deathspitter shots rained down on him. He finally fell at the beginning of turn 4. But he provided cover for the Kill Tank since it was able to act with impunity.
The Kill Tank was the player of the game. I ran it with a skorcha and twin big shoota plus the Bursta kannon. THe Kannon was awesome. Averaged 7-8 shots per turn and it brutalized vehicles every time it shot. The damage it caused with charges was also impressive and was a great way to give it cover from return fire or to finish units (I killed the Marine warlord by running him over after shooting the marine unit with shooting that was wrapping him).
The Burna bomma was great. It was able to kill 6 marines in one crater and 5 devastators in another crater next turn. Mortal wounds are terrific in that way. Its shooting was only so so though, with the plane picking off a few models here and there and really just chipping away at tougher things like the flying tyrant and vehicles. That 5+ to hit with his super shootas and only having 6 shots isn't great. I would suggest getting the burna rokkits though. Its more shots and does add to its anti-troop capacity. I have come around to thinking the burna bomma is the best choice for bomma. You aren't going to bomb vehicles as a rule, not enough impact. You will almost always use it on infantry, in which case the damage will be the same between both types of bombs.
Grot tanks were okay, but I found myself wishing they were killa kans. They were faster than kans, and they had a spare rokkit because of the kaptain, but it wasn't enough to mitigate the dangers they faced as they were charged twice. I had to charge a unit of ravagers at one point and it was a struggle. If I had had kans, it would have wiped them out. Similarly, they were twice charged by a tyrant. If he had charged kans, it wouldn't have been nearly as hard. He likely wouldn't have charged them at all. They are quite a lot cheaper than kans though.
Dakkajet did fine. Nothing special, but it did pour out plenty of fire and chipped away at plenty of models. Worked weill!