How do I get out of Limbo?

Hint 1 of 9:

Talk to the merman at the Fish Court.

Hint 2 of 9:

Find out how to bring back the Fish King

Hint 3 of 9:

at the Door to the Underworld.

Hint 4 of 9:

Collect an item which goes back in time:

Hint 5 of 9:

a newspaper (Dump),

Hint 6 of 9:

and an image of the Fish King:

Hint 7 of 9:

a coin (from the Blind Batfish at the Dump)