Discarding cards

From Archon Arcana - The KeyForge Wiki

The active player can discard from their hand any number of cards from the active house during step three of their turn. Cards are discarded one at a time, at any point throughout this step. This lets players remove cards that they do not want to play from their hand, freeing up space to draw more cards at the end of the turn.

Official rules v1.8 March 2021