Beat Pitfall Valley.
Temporal tower is in Pokemon Mystery Dungeon: Explorers of Time, Darkness and Sky, not Pokemon Platinum.
It has 50 floors and you find rayqaza at the top of the tower.
The Temporal Tower has 23 floors in "Pokémon Mystery Dungeon Explorers of Darkness."
99
mystifying forest
nothing
100
you go to jouyous tower and look for him =] (after story mode)
in the sky tower
Level40
You find it in joyous tower, on 50f, 60f, and 77f.
14 m8!