Should I use envirma or the regular version?

I’ve had the isle since it came out I think. Logged on a few times over the last several years, but I haven’t kept up with any of the news/ updates. I think I’ve only got 7 hours in the game, should I be using Envirma, or the regular game or legacy? Idk the differences but my buddy just got it and I want to get into it together. So where should I start and which version of the game is still getting worked on/updated?