Remove

The casting restriction is the entire design: this can only be cast during the declare attackers step, and only once a creature has already swung at you. That clamp turns a one-mana bounce spell (which would be an absurd tempo play if it could be cast freely) into a strictly reactive combat trick. You cannot bounce a creature in anticipation of an attack, cannot hold it for a value play later, cannot use it to save your own threat from removal. The card exists only to undo an attack that has already been declared against you. Portal was designed as a gentler on-ramp to the game, with simplified templating and a deliberate avoidance of stack-heavy interaction, and Remove embodies that philosophy by hard-coding its window directly into the text rather than asking a new player to understand priority and instant-speed timing. That is a narrow, almost training-wheels version of what bounce does in regular Magic, where the spell's flexibility is precisely the point. As a design artifact it shows how the same effect (return target attacking creature to hand) can be tuned from a swingy tempo tool down to a single defensive reaction by clamping the timing rather than touching the rate.