Special Summon Monster
Special Summon Monster is any monster that has a a rule or condition prevents it from being Normal Summoned as well as prevents it from being Normal Set. It often has a Summoning Condition that restricts how the monster must be Special Summoned. Therefore, most of those monsters considered Nomi or Semi-Nomi monsters.
Monsters with "Cannot be Normal Summoned/Set." [note] condition on their text are all considered Special Summon Monsters, as well as Fusion, Ritual, Synchro, and Xyz Monsters.
Notes
^ Monsters before Problem-Solving Card Text have "This card cannot be Normal Summoned or Set."
