The popular Red Purple Luffy choice in OP09 meta is the late-game approach, including high-cost cards to overpower opponents in the late-game
If the target permanent is an illegal target when Bahamut's third chapter ability tries to resolve, it won't resolve and none of its effects will happen
Notably, that +1 ability could create a single bug token, but if the cards in your deck are all lined up just so (and you happen to be running a lot of insects) it could create an unstoppable horde - and super early in the game too
Its not the most expensive summon though, which is an honor that belongs to a card which is coming soon below
Since these characters feature in a game, not a story, what happens to them varies from play session to play session
This looks like an absolutely fantastic Limited card