Eight legendary eggs spawn in specific Overworld biomes. Press F3 to read your current biome on the debug screen, then run /checkspawn to see which monsters can spawn there when using Cobblemon.
Biome-by-biome list
| Biome | Egg | Becomes |
|---|---|---|
| Old Growth Spruce Taiga | ZekromEgg | Zekrom |
| Old Growth Spruce Taiga | ReshiramEgg | Reshiram |
| Badlands | GroudonEgg | Groudon |
| Deep Ocean | KyogreEgg | Kyogre |
| Cherry Grove | ZapdosEgg | Zapdos |
| Ice Spikes | ArticunoEgg | Articuno |
| Dark Forest | YveltalEgg | Yveltal |
| Swamp | ZygarEgg | Zygarde |
Hunting tips
- Old Growth Spruce Taiga is worth visiting first, since two eggs spawn there.
- Deep Ocean hunting goes better with a boat. Potions of Water Breathing help too.
- Ice Spikes is a rare biome, so it may take some travel to find one.
- Write down the coordinates (F3) of every biome where you find an egg. You will need to come back later.
Why the biome matters later
Each of these eggs only evolves in its native biome, starting at Level 65. Train the egg in battle wherever you like. Once it hits Level 65 or higher, return to the biome where it spawned, and it will evolve there. For example, a GroudonEgg must be back in a Badlands biome, and a KyogreEgg must be in a Deep Ocean biome.