Yeah, for every finger it takes, it not only gains more fingers for the swarm, but lets say it also sucks the life out of them, turning them into undead and healing the swarm as a whole.

MitP vote: yes.

You scare me, DO. First the wombstrangler, then whatever it was that you named the sub-deific wombstrangler, now a swarm of necromantically animated fingers? I'm gonna pray for you later tonight, man. For like two hours.