During your Main or Battle Phase (Quick Effect): You can return this card to the hand, and if you do, Special Summon 1 "Kuribah", 1 "Kuribee", 1 "Kuriboo", 1 "Kuribeh", and 1 "Kuriboh" from your hand and/or GY in Attack Position
Counterfeiters find it nearly impossible to replicate it exactly
That is to say, while the various sets used one checklist for its cardssay, perhaps, Aquapolis Quagsire was numbered 30/147 Nintendo also kept track of e-Reader cards using their own systemthe same Aquapolis Quagsire had an e-Reader ID of C-38-#
The copied artifact stays in play, even if the original goes to the graveyard, which means a player can use it to get some pretty powerful artifacts on their side and gain the upper hand against more seasoned players with stronger decks
Early Days Collection received "mixed or average" reception according to the review aggregation website Metacritic
Of course, this cool new bug is a sideboard card, but it has applications in a bunch of older formats