Remember, these cards care about how much mana you actually spent on the spell, not the printed mana value so the higher tiers of Ice Magic and Thunder Magic, the flashback casts of Dreams of Laguna and Laughing Mad, and a big Syncopate or Choco-Comet will all work to trigger your stuff
You can play more than 40 cards, but I would strongly advise against it
-3: Destroy target creature or planeswalker
Reprint Chances: Likely (Whip-Spine Drake) and Unlikely (Lumithread Field, Whetwheel, and Zoetic Cavern) Sliver Cycle Slivers were another creation from Mike Elliott's Astral Ways set
While this card is not equipped with an Equip card, you take 0 battle damage from battles involving this card
Wattkid can fit well in a Watt-themed deck, which focuses on swarming the field with low-level monsters and utilizing their effects to control the game, particularly through burn damage and field control