Copycat

You learn to snatch components from spell casters as they are casting. If a spell caster casts a spell and you have enough movement to get to them, you can run up to them, grab their  component/components and cast the same spell they are casting. This uses your reaction, part of movement and action. No spell slot is consumed but you can only use whatever movement you have left and bonus action. This only works if the spell has a material component.