msem-instigator

Siphon (Each -1/-1 counter you put on your creatures up to their remaining toughness while casting this pays for {1}.)
Choose up to X, where X is the amount of mana spent to cast this spell —
• Target creature gets -3/-3 until end of turn.
• Surveil 2.
• Create a 1/1 black Bat creature token with flying and “This creature can't block.”