Medicus Lacus
From Archon Arcana - The KeyForge Wiki
Medicus Lacus • Saurian • Creature • Common • While the tide is high, you may spend on friendly creatures as if it were in your pool. • Artist: Konstantin Turovec • Card Number: DT:178
Commentary
If there is enough Æmber on Medicus Lacus (or other cards with this effect under the control of the active player) combined with the Æmber in the active player's Æmber pool during the "Forge a Key" step, the active player must forge a key.
Source: Forge