WMG / Pokémon X

Wally is the host/chosen one/whatever of Rayquaza
Some points:
  • Wally's obsession with green.
  • It rescued him from drowning.
  • The bizarre alt-voice speech bubbles Wally occasionally speaks in look very similar to the bubbles Groudon uses. Since Groudon's speech is red, it can be assumed that Kyogre's would be blue and Rayquaza's green.
  • Rayquaza is responsible for preventing Groudon and Kyogre from ripping the world apart with their fighting. In that same strip, Wally is the only one to notice Groudon rising. He removes the meteorite and prevents Groudon's awakening before saying something in the alt-speech bubble.

Wally is under Rayquaza's control
  • It's green, which might explain his obsession, he's been repeatedly hinted to be very strange and has acted to stop Groudon from freeing itself.