10. Quantum Bands (Marvel)
The Quantum Bands are the nearest thing Marvel have to a Green Lantern ring and they would be very easy to introduce to the Marvel Cinematic Universe, given their association with S.H.I.E.L.D. When the anti-hero, the Crusader, dies, he leaves the Quantum Bands unattended. S.H.I.E.L.D then spend time at a research facility running tests on them. A test pilot who was selected to wear the bands proves very successful in their usage, but he dies when the energy output reaches a critical mass beyond his control. S.H.I.E.L.D agent Wendell Vaughn puts the bands on when the criminal scientists A.I.M (who are already in the MCU) launch a full-scale assault on the facility. He repels the attack with the bands' power and when the energy build-up begins to overwhelm him as it did with the test pilot, he decides to simply relax and "go with the flow". To his surprise, the build-up abruptly dissipates and Vaughn realises that the key to wielding the bands is a flexible will, rather than an indomitable, uncompromising one essentially, his lack of a killer instinct makes all the difference. He becomes a hero and, after trying out a few names (Marvel Boy, Marvel Man etc), he settles on Quasar. As Quasar, he possesses the abilities of energy manipulation, teleportation, the creation of solid light constructs and flight. The bands being present in the MCU would give the Avengers and S.H.I.E.L.D a powerful new ally and the visuals that could be provided by its powerset would be stunning to see in live action.