Gaining a level on your Class is a normal activated ability
Not only is the art on this Mickey card absolutely gorgeous, but the card's effect is a great way to stun your opponent's characters to prevent them from questing next turn, making it a central part of Emerald's game plan
The prevalence of treasures and built-for-Commander legendary creatures inches the power level status quo higher with every set, and the release of dedicated Commander sets like Commander Legends: Battle for Baldurs Gate is always a volatile time for casual tables
It's arguably the weakest of the abilities among the dragons, meaning the only other real unique characteristic it has is haste, which, as a 5/5 flying creature, is very useful, but wouldn't necessarily cause an opponent to change their entire gameplay to deal with
If you can afford them, then you should probably pick them up
I also like this in Hate Bears with enough bodies to pump up and get a Commander Damage kill with level 3