Sigrid, God-Favored

Flash is what turns a 2/2 for three into an ambush: hold up mana, wait for the swing, and drop her in to exile the biggest attacker for as long as she stays on the board. The exile is the tempo swing, but the first strike is what lets her stick around afterward, blocking up into most early aggression rather than dying in the crackback. Because the exile is worded to last only until Sigrid leaves, the answer to her is to kill her in response to the entrance trigger: the trigger still resolves, but its duration has already ended, so nothing is exiled. That is the discipline on an otherwise disruptive effect. It is not the older Oblivion Ring template that would drop the exiled creature back as a bonus; here, removing Sigrid before her trigger resolves means nothing gets exiled in the first place. The protection reads as pointed era hate: against God creatures she cannot be targeted or blocked, though she can still block them herself and prevent their damage, which makes her a clean blocker against exactly the threats those planes leaned on. She belongs to the lineage of white ambush blockers built around timing and surprise rather than to the removal-spell school. Restoration Angel is the closest functional cousin, a flash body that swings a combat step; the moment you tap out for Sigrid on your own turn, most of what makes her good has already evaporated.