Melee weapon
Trigger: an ally misses every target with an encounter or daily attack
Target: one creature targeted by the triggering ally's attack
Attack: Strength vs. AC
Hit: "2[W] + Strength modifier damage. The triggering ally's attack is not expended."
Insightful Presence: "The triggering ally gains a bonus to his or her next attack roll against the target before the end of your next turn. The bonus is equal to your Wisdom or Charisma modifier."[MP2:86]
No Gambit Is Wasted is an encounter power available to warlords at 3rd level.
No Gambit Is Wasted was introduced in Martial Power 2
CharOp Evaluation: Good [Char-op Warlord]
This power lets your ally regain use their Encounter or Daily Power if they miss with it, and allows you an off-turn attack in the middle of it, and the Insightful rider makes it even better. This is good in general, and gets better if your allies have especially effective Dailies or Encounter powers, so take that into consideration.