Ⓢ Cannot be Special Summoned.
① If a monster effect is activated (Quick): Tribute this face-up card;
negate the activation, and if you do, destroy that monster.
● This effect is Mandatory. It can (and must) activate in any Step and any Phase,
including Damage Calculation, and even in response to a effect triggered by an End Phase discard.
● If 2 "Doomcaliber Knight" are on the field, when a monster effect is activated,
both are tributedm, and both "try" to negate that monster effect.
however, only the one with a Chain Link directly adjacent to that monster effect in the Chain
(the first to activate) will actually negate that Monster Effect.