This effect is similar to Release to the Wind, a nasty combo that started showing up in Pioneer a while back
In case you missed it in the flood of announcements a couple of weeks back, the Final Fantasy Holiday release will consist of four new Scene Bundles and the Chocobo Bundle
Any time a Pokmon gets that kind of promotional placement, collectors take notice
Its a great option to helm a storm deck that wants to use High Tide to produce a ton of mana, or a terrifying stax commander who breaks the symmetry of cards like Stasis and Winter Orb
It highlights new mechanics like Bending and returns to old mechanics like Experience counters and Allies
If, however, there are no legal targets for the Drag Below ability when Dragon Turtle enters the battlefield (or you choose not to target anything), Dragon Turtle's ability will still resolve and cause it to be tapped and it won't untap during its controllers next untap step