Martian Cows were creatures that Ratchet had to suck into a machine using the Suck Cannon. The machine turned them into crates which were required in order to win the Iron Lombax challenge on the Moon Cow Disease map. Ratchet had to create three crates from Martian Cows in order to complete the objective. In the PS2 version of Ratchet & Clank: Size Matters, the Martian Cows were replaced with the Dayni Weresheep.
- Ratchet & Clank: Size Matters (first appearance)