jaelis
Oh this is where the title goes?
So thank you everyone for the comments. As I hoped, they inspired my creativity (and I'm going to have to start a new thread haha).
But I do have a more... what is fair to the player question kinda deal. I just had a "aha! This is the perfect replacement patron" inspiration. I'll have to design the spell list etc.
But this may not be to the player's liking. What if they wanted something else for the new patron?
How would handle that?
Offer the player your new option, but if they don't like it, you can decide that the dead kraken becomes a vestige, with the player's pact as their sole remaining tie to existence. Even though they are adversarial, they would keep relying on each other for power. That way everything remains status quo ante.