Walking Ballista [Aether Revolt Prerelease Promos] 220 or triggered ability

or triggered ability

Set: The Lost Millennium Card type: Fusion/Effect Monster Rarity: Ultimate Rare Attack: 2100 Defense: 1200 Elemental Hero Avian' + 'Elemental Hero Burstinatrix' This monster cannot be Special Summoned except by Fusion Summon

during damage calculation: This card gains ATK equal to the current ATK of the opponent's monster it is battling during that damage calculation only

Set: Ra Yellow Mega Pack Card type: Synchro/Effect Monster Rarity: Super Rare Attack: 2600 Defense: 2100 1 Tuner + 1 or more non-Tuner DARK monsters Once per turn: You can target 1 monster your opponent controls

Walking Ballista [Aether Revolt Prerelease Promos] 220 or triggered abilitySet: Aether Revolt Prerelease Promos Type: Artifact Creature Construct Rarity: Rare Cost: {X}{X} Walking Ballista enters the battlefield with X +1 +1 counters on it. {4}: Put a +1 +1 counter on Walking Ballista. Remove a +1 +1 counter from Walking Ballista: It deals 1 damage to any target.