Siren's Call [Alpha Edition] Mountain Plains then reveals the top card

then reveals the top card of their library

its spinous hands To break the hosts that foul its lands

Set: Promo Finish: Cold Foil - Golden Type: Equipment Subtype: Chest Rarity: Promo Class: Guardian Once per Turn Action - [1 Resource]: Create a Seismic Surge aura token

Those creatures gain vigilance until end of turn

Siren's Call [Alpha Edition] Mountain Plains then reveals the top cardSet: Alpha Edition Type: Instant Rarity: Uncommon Cost: {U} Cast this spell only during an opponent's turn, before attackers are declared. Creatures the active player controls attack this turn if able. At the beginning of the next end step, destroy all non Wall creatures that player controls that didn't attack this turn. Ignore this effect for each creature the player didn't control continuously since the beginning of the turn.