Set in-between S1-E21 and S2-E1. Completely canon excluding the fact that Bobo doesn't exist.
It was a normal day at Providence. Well, as normal as it could be for a place centered around working with monsters and such. The secret weapon of their's, 16 year old Rex Salazar, walked happily along the halls. Behind him was Six, his partner and father-figure. It was an extremely simple mission. The duo was going to take control of a near-by E.V.O that just so happened to cause enough trouble to call in the two of them.
"So, what's the deal with this one?" the hispanic teenager asked his comrade.
"Partially invisible. Shouldn't be that hard to take care of," Six responded in his typical, serious tone.
"What the hell do you mean by partially invisible?" Rex snapped back, seemingly pissed off.
"As it completely straight-up says. The E.V.O can be temporally invisible."
"...Why."
"Do you think I am the reason for the Nanite Event?"
"...No."
"So Rex, this is the spot," proclaimed Six, looking around.
"Yeah, not like you're going to s-" Before Rex could finish his sentence, it hit him. The E.V.O was no more than a humanoid outline, although it seemed to shift to be nothing. "Damn thing asked for it!" Rex stated, as he quickly built his Smack Hands and hit where the creature was previously, but it was LONG gone.
"You have to be more on it," Six stated, as he managed to stun the E.V.O with a hit from his magna-blades. Gripping the monster with the Blast Caster, Rex began to cure the E.V.O when Six screeched with pain. Rex turned only to see his comrade on the ground, bleeding. He had been stabbed deeply in the back. Quickly curing the 'partially invisible' he had caught, he kneeled down next to his friend.
"Six! SIX! Are you okay!?" Rex said in-between his tears. The blood made Rex feel sick to his stomach. Quickly, he called into Providence. "Not sure who the heck picked up on the line, but get over to my location ASAP! Six is down, I repeat Agent Six is down and maybe dead!" he yelled into his communicator. He was relieved to quickly be responded to by Dr. Holiday, who was just as scared as he was.
"I'm sorry...Six...I'm sorry..."
It had been a few days after the incident, and it was probably the worst to happen so far. Not only had they been rebuilding due to the attack from Van Kleiss, but now they had lost one of their best members. Even White Knight was quite sad over the loss, and it was even worse considering Six's body had vanished. Rex had considered him going E.V.O, but he didn't know how'd it happen considering he was clearly dead. And that was when he was called into to care of an E.V.O, solo. One of tier 1.5 strength.
He had finally reached the location when he saw it. The creature was green, with large feathered wings. It stood only on back legs, with the part they connected to being much larger than the rest of the body. 6 talons managed to balance the entire creature between it's two feet(6 on each) and it's long tail ended in a smaller tip of fur. Connected via it's long neck, the head was dragonoid with the bottom and upper jaw seemingly split, a beak ending it's mouth despite the teeth within. It had smaller, pointed ears that seemed to make it look like a fusion between a dragon, bird and cat. It had 6 eyes, 3 per side, with the middle ones acting as the primary eyes.
"Come and get me!" Rex exclaimed, building the Slam Cannon and shooting the E.V.O. It dodged, but took notice on Rex and started flying in it's direction. Landing in front of him, it screeched and nearly pushed Rex back. It wasn't anything like what Circe could produce, but it sure was loud. Then, it stopped. Cocking it's head, it starred at the teenager.
"Rex...?" It seemed to communicate telepathically, and the voice was shockingly familiar. Rex couldn't put a grip on it for a second, but when he did, he was shocked.
"...Six?"