Number Wall

The activation of the card "Numbers Wall" can be performed at any time except during the Damage Step, provided that a "Number" monster is face-up in your Monster Zone.

The effect "As long as this card remains face-up on the field, "Number" monsters on either side of the field cannot be destroyed by card effects, and cannot be destroyed by battle except with other "Number" monsters" is an effect that does not create a Chain Link. (This effect is applied not only to "Number" monsters that were present when "Numbers Wall" was activated, but also to "Number" monsters that are Special Summoned afterwards.)

The effect "When a "Number" monster you control is destroyed: Destroy this card" is an effect that does not create a Chain Link. (This is also applied during the Damage Step.)