Of course, that set sold out immediately as well
Complete Sets: Collectors often seek to complete their sets, which can increase the value of individual cards
The major difference is swapping out Hitmontop for Darkrai, which synergizes with Igglybuff's ability to put the opponent's Active Pokmon to sleep
Yes, this is a lot less common than a creature gaining shroud, but players can indeed get shroud

Keep in mind I dont think it is complete, meaning it will be changing as I test new stuff: Monsters (23): 3 Sylvan Hermitree 1 Blaster, Dragon Ruler of Infernos 3 Sylvan Sagequoia 2 Fallen Angel of Roses 3 Sylvan Marshalleaf 2 Lonefire Blossom 3 Sylvan Komushroomo 1 Spore 1 Sylvan Peaskeeper 1 Sylvan Cherubsprout 3 Sylvan Princessprout Spells (12): 1 Soul Charge 2 Terraforming 1 Foolish Burial 3 Sylvan Charity 3 Miracle Fertilizer 2 Mount Sylvania Traps (5): 2 Vanitys Emptiness 3 Call of the Haunted Extra Deck (15): Synchros: 1 Scrap Dragon 1 Stardust Dragon 1 Stardust Spark Dragon 1 Black Rose Dragon 1 Armory Arm XYZs: 1 Hieratic Sun Dragon Overlord of Heliopolis 2 Divine Dragon Knight Felgrand 1 Alsei, the Sylvan High Protector 2 Orea, the Sylvan High Arbiter 1 Mecha Phantom Beast Dracossack 1 Number 11: Big Eye 1 Evilswarm Exciton Knight 1 Temtempo the Percussion Djinn So, without Soul Charge, what do we have here