I think the Snuffler buff is for Moonclan units
So ideally you deepstrike the Snuffler 9 inches away from the enemy, release 15 fanatics 3 inches away from the carrier, buff them with the Snufflers buff, and if you can get COGS off they just have to make an 4 inch charge, once you activate them in combat, they get 15 + 15 D6 attacks off ( Edit: if under the moon they get rerolling 1 to hit)