a handful of arm suggestions.

[BlackPhoenix]

they need to turn ridiculously violent to the point where even if they try to do good they cause problems

like, if you try to help someone up, you end up stabbing them with the saw, or if you try to open a door, there's a small chance you'll stab through the door and get electrocuted through the chainsaw

also, make it impossible to use guns and make even using medicine or food difficult

This is dumb, they still have a regular hand.

Now, if they replaced both hands with chainsaws, maybe that could be a problem.

I would love to see you try to fire any gun with one hand and be even mildly accurate.