The Latios's radiation is lethal and highly contagious. Their desire is to KO off all other pokemons.

The Latios starts the game with mega stones that carry the eon. They have one mega stone for every five pokemons in the game (rounded). If there are several Latioss then they know each other and their mega stone counts are combined. Each Latios may use one mega stone per night. Each night, the Latios may free one of their mega stones to contaminate another pokemon. Contaminated pokemons will be affected by the radiation. The Latios cannot be contaminated. If the Latios attempts to contaminate an already contaminated pokemon, they are informed, but the mega stone is still used up. Contaminating a pokemon is an immediate ability. Any pokemon who visits or is visited by a contaminated pokemon immediately becomes contaminated themselves. All types of action (target, attack, investigation, etc) are considered visits. At the start of the second night after being contaminated, the pokemon is informed that they are contaminated.

At the end of the second night after being contaminated, the pokemon will faint. This is not an attack. Should the pokemon still be alive afterwards, they remain contaminated, and will faint at the end of the next night. If no members of the eon team or channel remain, all pokemons stop being contaminated: they are not informed of this. If the Latios attempts to use a mega stone on the Vacation Pikachu, the attempt fails, the Vacation Pikachu immediately faints (this is not an attack), and the mega stone is not used up.