Cards like Teferis Moat, Raking Canopy, Elephant Grass, Ghostly Prison, Arcane Denial, Mindclaw Shaman, Syphon Mind, Relic of Progenitus, and Nevermore can play different roles in stopping a certain type of plan or play from coming to fruition
What set is Reaping the Rewards from
Damage that a creature with infect deals doesn't result in damage being marked on a creature or a player losing life
Demonic Tutor is by far the most iconic and most reliable of the lot, not subject to deck shuffling shenanigans like Vampiric Tutor
Grazilaxx, Illithid Scholar This isn't exactly the Ninjutsu type of effect, but it is somewhat similar, and allows you to exploit some powerful ETB effects over and over again
Alternatively, you can just Fling your massive Strong at an opponent for a different flavor of instant win