SPOILER DISCUSSION
1.I’m of the opinion that “it” is very much alive and didn’t die in the third act. All the demonstrations from before prove that after taking damage it has a small recovery period. After getting shot on the beach, it slowly goes down before coming back up. The damage from the pool is probably significant enough to keep it down for longer and it’s back at the end coming towards Jay and Paul. A sequel with Paul being brutally killed and Jay being forced to find a way to stop it could be cool depending on the way they go about it, but I’m happy with the ambiguous ending.