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That seems like he is wrapping his clothing (claws?) around the opponent? Combat Tentacles might apply to that specific scenario because they seem to be extending and controllable. Bear Hug may have applied if there wasn't any extension of limbs.
My Deviant Art account. There might be art there. Sometimes.Shapeshifter Weapon seems to be the {Golem?}'s method there, but I'm kind of surprised to not find one for "larger opponent incapacitates smaller opponent by grabbing them"
Do we have a trope for a character being attacked by being squeezed/squashed? I mean the thing that's hapenning in the last panel here.