Cling to Dust A cantrip that exiles a card from the graveyard is pretty solid
Vanquisher's Banner and Icon of Ancestry work like this, giving all your Goblins +1/+1, but the more Goblin lords you control, the more of a threat your swarm of 1/1 creeps will be
They're for your deck, and will be used by you, hopefully frequently, so why not choose something you enjoy
Like Creature types, the Lesson subtype doesn't have any effect on the mechanics of the card but instead allows other cards to refer to and interact with them specifically
5 Scourglass A one-sided board wipe that almost always works in your favor, Scourglass is a unique artifact that decimates the battlefield if not answered by your next turn
Before a card is released it is difficult to predict how it will perform, how the masses will use it, or even how it will be perceived for other merits or shortcomings