This is news?

The explanation of the feature in this game is a bit late.  The game released over a month ago, and the story has several things that are false.

Beast Possessions is one of the main features of the game.  Although we have seen this type of feature before were when a person reaches a certain limit in battle they can transform into a stronger version for several minutes; Requiem adds its own flare to this.  You get several beast possessions you can use after doing a storied quest that sets you into a dungeon to claim it from ancient technology.  Each possession offers a differen't type of playstyle and you need to level it up in order to benefit from it.  The possessions also can equip armor that gives additional skills, they are obtainable from nightmares above level 23 or the Auction House.  After putting the ones you want into your 3 beast possession slots, you can choose how exp is split among them.  Such as you can split it evenly across all 3 possessions, or you can put it all into your favorite.  EXP is gained passively in combat in or out of beast possession form.  Also there are plans to add more beast possessions with updates.  The next one adds a dryad type possession.

The benefit is you can be a Mage, but in combat switch to a Melee Beast Possession.

I think they need ot fire their marketing guy and hire you Cleffy.  At least you made some sense.