Bubbling Muck
When Unwilling Vessel dies, create an X/X blue Spirit creature token with flying, where X is the number of counters on Unwilling Vessel
PS Platinum Secret Rare QCSE Quarter Century Secret Rare Madolche Puddingcess X EARTH Level 5 [ FairyEffect ] ATK 1000 DEF 1000 Gains 800 ATK/DEF while you have no monsters in your GY
On the other hand, Nightveil Specter can steal lands, which is a nice upside, but because it was printed nearly a decade ago, it doesn't fix our mana for the cards it steals (it's our only theft card that doesn't), so we either need to hope that our opponent is playing blue and black cards that we can cast with our mana base or hope that we can use Nightveil Specter to steal some lands of the proper color before moving on to casting nonland cards
Like most Pokmon cards, the value of Latias depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Delta Species)
While the mechanic does appear to be enjoyed by fans, Wizards of the Coast doesnt often print Meld cards
