As Sparky can deal loads of damage, it’s recommend to use it as a support troops behind meatshield such as Golems, Giants, P.E.K.K.A,…
When used incorrectly, Sparky’s damage is usually wasted on weak troops (Goblins, Skeletons,…). Make sure you pcouple it with splash damaging troop such as Bomber, Princess, Wizard,… or at least Zap/Fireball.
Guards and Dark Prince can easily counter the Sparky. Due to their shields, they easily survive the first Sparky’s hit and take it down right after that.
When you place Sparky, it will take 1s (deploy time) + 5s (load time) = 6s to do the first hit so make sure it is not attacked while loading.