The 5th level Desert Wind counter Leaping Flame allows you to teleport to an enemy within 100' that attacks you with a melee (which is useful if the enemy has reach, or if you need to quickly grant somebody a flanking bonus) or ranged attacks. This is highly useful - and as far as I see, it even gives you the "enemy is there" button against invisible/hidden attackers (like a short-sighted sniper who thought it would be wise to attack you from a 100 ft distance). Through, that brings us the question - are there combat situations in which Leaping Flame is useless? What are they?
What if the enemy uses a spell that deals no HP damage, like Touch of Idiocy? Or a Battlefield Control spell, like Solid Fog/Grease? What about delayed/continious damage effects like Acid Fog? And how about attacks that require no attack rolls like Magic Missile (or Power Word Pain (link will be later)?