What is the artfact and creature that lets you play a creature card without paying its mana cost
{Elvish piper} {quicksilver amulet}
{Æther Vial}, to an extent.
Try using the filters in the card search database.
{Elvish Piper}
{Quicksilver Amulet}
{braids conjurer adept}?
{Omniscience} if you want more than just A CREATURE.
{Kaalia of the vast} works too