Petra Sphinx [Legends] Artifact Creature Sliver spells you cast have

Sliver spells you cast have cascade

Set: Classic Sixth Edition Type: Artifact Rarity: Rare Cost: {4} At the beginning of each player's draw step

you may discard a card

Creatures you control can boast twice during each of your turns rather than once

you may play that card

Petra Sphinx [Legends] Artifact Creature Sliver spells you cast haveSet: Legends Type: Creature Sphinx Rarity: Rare Cost: {2}{W}{W}{W} {T}: Target player chooses a card name, then reveals the top card of their library. If that card has the chosen name, that player puts it into their hand. If it doesn't, the player puts it into their graveyard. What walks on four legs in the morning, two legs in the afternoon, and three legs in the evening?