I'm starting to think there's two possible tropes here. One about opposite absolute forces, and one about the use of "unstoppable force meets immovable object" as a Stock Phrase. I need better titles for both.
Two diametrically-opposed forces exist in the same 'verse
. Both forces are stated to be absolutes. Naturally, someone (if not in the story, then in the fandom) will wonder what happens when the two forces clash
There's two conceivable outcomes of this hypothetical clash:
- One (or both) of these forces proves to be less absolute than advertised. This can play out a few ways:
- One of them is simply stronger.
- Both of them destroy the other, which could be interpreted as a win or a loss for both of them. For example, when you block the Unstoppable Sword with the Unbreakable Shield, both will simply break.
- Both of them remain completely evenly matched until some outside force intervenes. Sealed Evil in a Duel works on this principle.
- Both these forces are absolute, and the logical paradox destroys the universe.
- Shield and Sword from Suikoden: Shield can withstand anything, and Sword can destroy anything.
- The X-Men foes: The Juggernaut's superpowers boil down to being an Unstoppable Force, and The Blob's powers boil down to being an Immovable Object.