This particular Grovyle made his first appearences during the first few days of the thread, but disappeared for a time. Where he went remains to be a mistery, but since his disappearence his skills have sharply increased.
The Early Days
Jason first arrived as a drifter, wandering from place to place in search of obtaining more power. That goal would soon guide him to Samurott, where he'd become his second apprentice and train under him. It's also noted that Jason resided in Zangoose's hideout, and had his own room. He had also met up with Shilk, almost instantly recognizing each other from their alternate universe.
It was also revealed that Jason seemed to know of Nightshade, but she herself had no recollection of him, but only of her two team members. He would persue her, and vainly try to jog her memory, something that was met with failure. However, in a choice between him and another absol, she had chose him.
While planning an expidition to the Mirrage Tower, he mysteriously vanished ithout a trace.
Across The Multiverse 
Based on multiple interactions with Shilk, Jason gives off hints that he seems to retain memories of an alternate version of himself from a different universe, but not vise versa. It remains to be unknown how he has this knowledge.