309.4a As a player puts a dungeon they own into the command zone, they put their venture marker on the topmost room
And it works on any form of leaving the battlefield, so you can bounce or exile or even shuffle it into your library, so it works with effects as diverse as Terminus, Fleetfoot Panther, and effects like Goblin Bombardment and Crystal Shard
While youre here, you can also buy some neat Relics of Wizardry trinkets, like metal -1/-1 counters or a Monarch marker
When combined with Reunicluss Damage Swap , used to spread the damage from your Active over your bench, you can heal up to 60 damage with this every turn
During this time, everyone received a reasonable amount of support in the form of these gimmicks, but Fairy-types were not so lucky