Modern Emerald Randomizer: How It Works In-Game

Modern Emerald's randomizer is built into the game — no external tool, no patched ROM. You enable it in the new-game menu on the Randomizer page, and it is "completely modular", so you choose which systems get shuffled rather than flipping one master switch.

What you can randomize

Wild Pokémon, trainer teams, items and more, each as a separate option. Because it works from the game's own data, the same 436-species roster is what gets shuffled.

What is not randomized

The author notes that some special or particular Pokémon may not be randomized for technical reasons — expect the scripted encounters (starters, legendaries, gift Pokémon) to be the ones that keep their identities. Everything in the normal wild and trainer tables is fair game.

Interactions worth knowing

• Wonder Trade unlocks from the start on a randomizer save instead of after the fifth badge, and randomizer saves can also be configured to randomize only after you beat the game.
• The challenge options still apply. A randomizer run with level caps and one-type-only is a real format, and the Battle Frontier Pokécenter NPC can turn challenges back off if the combination stops being fun.
• Nuzlocke works on top of it. Species-lock clauses are irrelevant when the tables are shuffled, so most people run randomizer Nuzlockes with dupes clauses relaxed.

Randomizer description and behaviour from the hack's official feature list; roster size from the extracted Pokémon data.