Pokémon Zeta is a fangame for the main series of Pokémon RPGs. It begins as the player character escapes the destruction of their hometown in a terrorist attack by Team Asgard, and follows them as they journey through the Vesryn region. Along the way, they fight Team Asgard to avenge their home and save the world. A second scenario, unlocked after beating a difficult challenge in Vesryn, sees the player start a new journey in the Aroma region. Here, they must rescue corrupted Shadow Pokémon.
The game contains the first 649 canon Pokémon, a few additional ones that were introduced in Pokémon X and Y, and a handful of original designs. Gameplay and graphics are largely based on the DS Pokémon RPGs. Like official Pokémon RPGs, Zeta is paired with another game, in this case Pokémon Omicron.