I think it would be cool to add a alien monster thing. it could be in a cage and its limbs hit the robots or something like that.
Human! You are about to become a sword robot! · By
First thought reading this was a giant squid in Super Mario Sunshine. In the harbour area.
While in that mode you pull off the tentacles, perhaps the horizontal slash could take off the tentacles while rotating or something like that.
The squeezing idea sounds like it would be an insta-kill unless you have some "degradation" concept planned. Choreograph also sounds like it may be difficult.