Biased Invocations

Whenever you cast an instant or sorcery spell,
create an X/X colorless Knight artifact creature
token, where X is that spell's converted mana cost.
{3}{u}{u}, Exile Biased Invocations:
Return all instant and sorcery cards from your graveyard to your hand. Activate this ability only
if you control six or more artifacts.
More and more the dungeon turned blue, and one
could hear rallying cries on the horizon.