Considering the relatively low ink cost of all three Ducktails nephew cards, getting this ability rolling early on in a Lorcana game is entirely plausible, as well as being excellent gameplay-wise thanks to the advantage that additional card draw can get you
Your collection stays private by default
Yarok, the Desecrated Yarok, the Desecrated is just Panharmonicon in the command zone, but supercharged since it doubles landfall abilities as well
While Eidolon has a creature version of Pyrostatic Pillar, a powerful burn card in its own right, Cemetery Gatekeeper is like a more flexible creature version of Ankh of Mishra
Whenever one of your dragons is targeted by a spell or ability, you get to blow up a nonland permanent your opponent controls
Spend this mana only to cast a noncreature spell