Once per turn: You can destroy as many Field Spells on the field as possible, and if you do, gain 1000 LP, then you can add 1 Field Spell from your Deck to your hand
However, it requires you to have "Uxie" and "Azelf" on the Bench at the same time and burns off all of the attached Energy, making it not only very difficult to set up but also makes "Mesprit" extremely vulnerable even if it one shots a Pokmon ex
Gardevoir is regarded not for its stats or moves but rather, its phenomenal Ability, Psy Shadow
So, by carefully picking the Pokmon selected for the breeding process, you can greatly increase the odds of watching a Shiny Pokmon hatch from that egg
It all sounds similar to your standard Dominaria / Dominaria United / Kaldheim / etc