- "Fighting this metal monkey will result in quite the experience. Just keep that in mind."
- — Battle Memory
The Mystery Metal Monkey is an enemy that appears in Mother 3. It can be rarely encountered in Argilla Pass, in a cave near the Negative Man's; it can also be found outside the cave, and on the path to the nearby Hot Spring. Approaching the Mystery Metal Monkey makes it get up on its hind legs and run around.
The Mystery Metal Monkey is completely immune to PK Freeze and PK Fire, but PK Thunder and PK Love can inflict sizable damage. Because of its absurdly high defence, physical attacks will only inflict 1 point of damage.
As indicated by the Battle Memory, the text "It was a good experience!" appears in lieu of actual experience points when the Monkey is defeated. It drops a Made-You-Look 20% of the time.
Its battle sound is Battle Sound 52 which falls under Code Numbers 915 for regular attack, 916 for Smaaaash! and 917 for Miss.
- The Mystery Metal Monkey is a parody of the Metal Slime from the Dragon Quest series, as both are elusive, metal creatures. The fact that it gives no experience and instead lists the phrase "It was a good experience!" is a joke based off of the fact that Metal Slimes are sought after because they tend to grant 1000 experience points or more, which is why the Mystery Metal Monkey does not give experience points.