This won't derail the act in the same way dropping the card could
Her 'The Singing Sword' ability also lets her challenge ready characters whenever you play a song on your turn, so there's basically no escape from her blade
Despite the effect of transforming Battle being a triggered ability , its controller exiles the permanent and then casts it without paying the mana cost , opening up space to interact with Battle on the stack with Make Disappear, or other counterspells, or even to bounce them on the stack, with Venser, Shaper Savant and the like
It is also protected if it somehow finds itself on the Bench getting hit by a bench-hitting Move
Plus, it even lets you Scry 2 whenever it enters the battlefield
The key to success is low investment : Lickitung is an obviously terrible card, but throwing out a Misty or putting an Energy on an Eevee youre building up to evolve anyway is a small cost with high potential reward