Effect
Cannot be Special Summoned, except with a "Ninjitsu Art" card's effect. Spells/Traps you control cannot be destroyed by card effects.
"Must be Special Summoned with the effect of a 'Ninjitsu Art' card" is not treated as a monster effect.
"White Dragon Ninja" can be Normal Summoned, but if it is to be Special Summoned, it must be Special Summoned by the effect of a "Ninjitsu Art" card. (This also applies if it is being Special Summoned from somewhere other than the hand.)
"While this card is face-up on the field, Spell/Trap Cards you control cannot be destroyed by card effects" is a Continuous Effect.
Spell/Trap Cards face-up on the field of the controller of "White Dragon Ninja" cannot be destroyed by card effects. (Face-up Field Spells in the Field Zone and Pendulum Monsters in the Pendulum Zones also cannot be destroyed by card effects.)
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