Champion animation for destroying rek'sai's tunnels?

im sure everyone has noticed by now that when you stand on a rek'sai tunnel to destroy it, (and assuming you arn't performing any other action except idoling) your champion does a special animation. none of the ones iv seen look particularly familiar, but in the heat of combat its hard to really analyze something that takes only a split second. so my question for the rioters is **"what pre-existing animations were used for the rek'sai's tunnel destruction." **if the animations are not pre-existing, (which i doubt) did you guys really go through and make 100+ new animations for EVERY champion?

follow-up question regarding new champion animations... it seems like a heavy work load to add in a new animation for every single champion in order to introduce a new mechanic (EX: the channeling animations used for dominion) my question is "what are the chances that a new mechanic could be added to the game at some point that would call for such new animations for EVERY single champion/skin?" and "does a work load this size deter the introduction of new mechanics that would require a set of new animations?"

as always, thanks for all the hard work