Break Through the Line

A repeatable evasion engine gated by a power ceiling, and that ceiling is what keeps the activation cheap. The power-2-or-less clause locks the enchantment out of greasing your top-end threats and ties it to the small, recurring bodies that go-wide red floods the board with. The haste rider does as much work as the unblockable one: on a freshly cast one-drop it converts a creature that would otherwise sit out the turn into immediate, untouchable damage. The real strategic axis is repeatability paired with pre-combat planning. Because "can't be blocked" has to be applied before the declare-blockers step, you are not reacting to the defender's choices so much as preempting them: hold up the mana, then before blocks pick which attacker most needs to slip through, whether to guarantee damage or to land a particular combat trigger. The opponent declares blocks already knowing one of your creatures is off the table. The power restriction is a target requirement, so it gates who the ability can point at, but it stops caring once the ability resolves: nothing prevents you from making a small creature unblockable and then pumping it past 2 power afterward with combat tricks or equipment, turning a swarm-support enchantment into the delivery system for a single lethal swing. Left to its own resolution it stays a tool for armies of uniformly small attackers, where the question is never raw size but whether any of them can be profitably blocked; bolted to a pump effect, it becomes a way to make exactly one of them too big to matter.