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"A construction Chimera designed to destroy the old Chimera Lab to make way for a new building."
Battle Memory

The Steel Mechorilla (てっきゅうメカゴリラ Tekkyuu Mekagorira; lit. "Iron-Ball Mechagorilla") is a boss in Mother 3, found at the top of Snowcap Mountain in Chapter 7. It resembles a gorilla whose hands were replaced by two steel balls and its ears replaced with radio antennae. According to Boney, it is a mechanical chimera.

Main History[]

After the Masked Man pulls Lydia's Needle in Snocwap Mountain, he flies off and releases the Steel Mechorilla to attack Lucas and his group.


The Steel Mechorilla is weak against PK Flash and PK Thunder; however, using PK Thunder more than twice will cause it to short-circuit and go berserk, attacking all party members every turn for a higher amount of damage than before.

His battle sound is Battle Sound 60, a battle sound used only by large bosses, which falls under Code Numbers 939 for regular attack, 940 for Smaaaash! and 941 for Miss.


  • As his Battle Memory text states, the Mechorilla was created to destroy the first Chimera Laboratory. It is unknown whether the Chimera Laboratory that Lucas and co. visit is the old or new building.
  • It is possible to fight the Steel Mechorilla without Kumatora, making the battle significantly harder.
  • There is a sprite of the Steel Mechorilla facing north, although this is not used in-game.
    • This makes the Steel Mechorilla one of 8 bosses to have unused back sprites: implying that it may have been a standard enemy at some point in development.
  • It appears to be loosely based on the character Ro-Man from Robot Monster: a 1953 science fiction movie.
  • Oddly enough, although Lucas only fights it because it attacked him, if he loses the fight he still has to go back and defeat it, rather than simply searching for the next needle.