In everyday, in starry night
You think you know what's wrong and right
Mess with us and feel their might
Back off or face our elemental blight!

-Gray Lantern Corps.

Interesting.

The Gray corps can do one of a number of things... nullify other colors. Shoot us with a beam from your ring? It'll just dissipate before reaching us.

So basically they're the Blue Lanterns when it comes to Blues going against Red or Yellow.

Yeah but it's against all colors. And this is merely my head canon,

Noted.

blue lanterns can't- They don't make energy projections

AHEM. That is incorrect. Borrowing some quotes from the Wiki, "While hope is the most powerful of the seven emotions, Blue Lanterns must be near an active Green Lantern's power ring to tap into their own rings' full power. Otherwise, the rings are only capable of the default abilities of flight and a protective aura."

"The Blue Lantern's protective aura allows them to survive in space and other hostile environments and can be manipulated to a limited degree even without a Green Lantern present, using it to augment their strength and extending it to form a larger shield, but this ability is almost exclusively defensive."

"While under the influence of a nearby green power ring, a blue power ring has the same abilities as a green ring, plus some unique powers of its own."

Blue Lanterns normally cannot, yes, with some exceptions. Unless in the presence of a Green Lantern. So unless I'm colorblind, I'd say his sparring partner grants him that ability.

The Furse is strong with this!

Space hijinks aplenty, even if from a different space-verse

nice