Petra Sphinx [Legends] Rivals of Ixalan Prerelease Promos put a -1/-1 counter on

put a -1/-1 counter on enchanted creature

Juggernaut can't be blocked by Walls

Set: Tempest Type: Artifact Rarity: Rare Cost: {1} {3}

its controller reveals cards from the top of their library until an artifact or creature card is revealed and exiles that card

if Clockwork Avian attacked or blocked this combat

Petra Sphinx [Legends] Rivals of Ixalan Prerelease Promos put a -1/-1 counter onSet: 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?