So what's the best way to approach mimetic aro pieces like the posthuman snipers/ karhu/kamau/frontovik or even a q drone? So far I am leaning towards the good old charontids but I am curious how do you approach them. Yaogat msr, suiciding skirmishers with shotguns or just work around them? If it helps, I am hell bend on trying out the bultrak so these gun fighters will be more of a supporting role to the bultrak
Do they have MSV? If they don't, smoke and deal with it later. If they do, hit them with something hard and oversized: Charontid works most of the time, that Yaogat B+1 Sniper might work too, but you don't even need to use a model with MSV. Hit them with a Rasyat from behind. Smash their face with a Speculo dropping two shotgun templates out of impersonation. Use your own mimetic models to even the field. It really depends a lot on the situation. I routinely kill posthuman snipers by hitting them with a Chainrfile template from a warband (daturazi are your friends). And I once had a rasyat dismantle a whole frontovik fireteam by throwing eclypse smoke on top of them then walking in and stabbing one by one. We also have a lot of models that can brute force the problem. Sheskiin does it, the Avatar does it, an Anathematic can do it, and so on. Sometimes the solution really is just 'shoot it until it dies'
Also, Camo or Impersonators against targets without Sixth Sense. Against, say, a Malignos or a Noctifier shooting from Camo typical TR drone will shoot back at 2's. Not so great odds, even with four dice.
You're 100% right and this is a good tactic. However, I've had a TR bot score not one, but a whooping four crits on a two (crit twice on two orders) on my noctifer recently and I'm still very salty about that.
If you want to absolutely, positively delete an aro pice - take the avatar, it's the best we've got against anything at 16"-32" range, and you don't mind if it gets hit a couple of times with anything other than AP+DA/AP+EXP and E/M, ARM12 in cover lets you tank a lot of hits from most of the weapons. On a less extreme points investment side of things - speculo with boarding shotgun is your friend, if you put it into reserve you can place her right where you need 2 DAM14 auto-hits delivered, though it won't help much against camouflaged aro pieces, but for that there's a MSV3 HMG charontid.
I can't speak for vanilla but in MAF I love me a gaki-torpedo. On a standard 12" dz it takes me between 2 and 4 orders to position the gaki within 12" for a berserk (that can climb). A lot of times it explodes on the way in too which is great for multi-wound ARO pieces. And remember you can always coordinate shots, this ruins most ARO pieces, especially if you can include blitzens (rindak), flamenspeers (kaitok) panzerfaust (yaogats) etc.
Honestly, with the link changes any decent gun can attempt even a Kamau. However, only the better guns or visored guns have good odds - a Bultrak is slightly better than a coin flip, with a 1/3 chance of nothing thrown in which is pretty inefficient. However, it can also tank return fire and repair until he takes it down. I felt the autocannon option was better - tiny bit worse odds, but if it hit the Kamau would vanish rather than KO or guts prone. I ran some dice calculations and found the Maakrep and Sheskin pretty acceptable (around 38% and 37% vs 15% and 18% respectively) against a fully linked kamau. Getting in under 16" with the right gun, or attacking through a forest or other saturation zone, pushes the odds way up. Bit plus a guided missile launcher is an inefficient but pretty unstoppable way to deal with these things. Think of it like a floor, a minimal but consistent way to make something go away. You'll spend a lot of your turn making it happen, but that sniper is gonna be fucking gone afterwards.