If revenge is on his mind, Jim and Harvey will probably need to watch out after their roles in his father’s death.
If he’s more into general murder and mayhem, the entirety of Gotham City could be in big trouble.
If the Gotham version of the character resembles the DC Comics version of the character, we have to expect that he has recovered at least enough to start plotting.
A big question is how much Crane has recuperated since we last saw him.