After Generate League

After Generate League is the first regulation format which only uses cards from Reincarnation Saga.

Details
It allows the following sets;
 * DM-14 Generate Gear
 * DM-15 Secret of Hidden Gear
 * DM-16 Origin of Perfect Gear
 * DM-17 The Over-Technocross
 * DM-18 Best Challenger
 * DMC-27 CoroCoro Dream Pack

It was designed as a new format to allow easier access to the game and tournament play by newer players.

However, due to the card strength of Bolmeteus Sapphire Dragon, Sapphire Fang decks dominated the metagame, with the environment being known as "Sapphire Hell".

After these events, format based tournament regulations were not tried again for years until the Awakening Saga block.