Ancient Gear Ballista

2 EARTH Machine monsters If this card is Link Summoned: You can add 1 ""Ancient Gear"" monster or 1 ""Geartown"" from your Deck to your hand. You can target 1 Spell/Trap you control and 1 face-up monster your opponent controls; destroy that card you control, and if you do, change that opponent's monster's ATK/DEF to 0 until the end of the turn. You can only use each effect of ""Ancient Gear Ballista"" once per turn.