If a Pokémon is frozen and acquires this ability, it will immediately thaw out; this includes when regaining a lost ability upon leaving battle.
Out-of-Battle Effect
If any Pokémon in the party has this ability, each egg in the party has its hatch counter decreased by 2 (rather than 1) each step cycle, making eggs hatch roughly twice as quickly. This effect does not stack if multiple Pokémon have this ability or Flame Body.
Pokémon with Magma Armor as a standard ability (4)