EpicDuel has gone through multiple different phases, known as "Development Phases."
Here is a brief on each phase in general terms:
ALPHA was the first public release and is classed as a testing phase where the games' core engine and gameplay was tested out. A normal Alpha phase tends to contain multiple bugs and is purely meant to really test the servers capabilities as well as multiple other things that cannot be tested in private developer testing!
BETA was the phase that followed Alpha and Beta testing tends to bring a much more stable build to a game, but still is classed as a testing phase, and may contain a couple of bugs. A game enters Beta testing to build up to the full stable game release later on after all possible issues have been ironed out.
GAMMA, DELTA and OMEGA were the next 3 phases.
In EpicDuel, all players who played through the different phases have had the option to purchase the relevant achievement for that phase as well as possible phase only gear. Gear and achievements from past phases, including but not limited to Founder Armour, Beta Battle gear, Gamma Bot and Bike and Alpha Weapons, will NEVER be returning and are considered permanent rares.
Some achievements such as ELITE and FOUNDER also will not be returning, since these are also classed as phase achievements. Elite was an achievement awarded to those who upgraded in EpicDuel's years before merging with Artix Entertainment while it was in its Alpha Testing phase. Founder is for those players who upgraded early in its Beta phase just after its merger with Artix Entertainment. Founders have a special bike and armor for their early support of the game and Elite's have received multiple perks such as an achievement for their very early support of the game! Once again, these items will not be returning, the same applies to the Gamma, Delta and Omega gear.