Olden Era is an old-school fantasy card battler built around assembling a warband and conquering ten citadels. Players combine one warlord with nine beasts, develop their cards, and face strongholds offering Raid, Siege, and Onslaught encounters. Warlords progress through eight ranks, unlock elemental spellbooks, and can be refined to improve their combat strength.

The game also offers competitive and cooperative activities. Players can enter the monthly Crown Tourney, send warlords on expeditions, assign squads to mines, complete quests, and join Pandora, where hunters fight a shared Warden and divide a common reward according to damage dealt. A player-to-player market lets users trade cards, while the in-game economy uses gold for summons and $OEM for activities such as forging, upgrades, and marketplace transactions.

Players can earn $OEM through battles, expeditions, mines, quests, tournaments, and other game features. The project states that eligible tokens can be withdrawn as USDT or USDC, subject to minimums and manual processing. Olden Era supports account access through Google and says there is nothing to install.