"Greed" (強欲Gōyoku) is series of cards whose effects revolve around drawing 1 or more cards from the player's Deck. All the cards in this series are based on "Pot of Greed", which lets the player draw 2 cards from their Deck; "Pot of Greed" appears in many of the cards' artworks. Other cards change this effect by increasing or decreasing the number of cards drawn or letting the opponent draw cards instead.
While the card-drawing aspect is similar, this series is unrelated to "Treasure Cards".
The storyline of "Goblin of Greed" can be seen in the artwork of the following cards:
Also, there is a related series of "Pot of" (な壺, na Tsubo) Normal Spell Cards that are directly reminiscent of "Pot of Greed", either in terms of effect and/or artwork and concept, and that have the effect of allowing the player to draw 2 cards, with the difference between them being the cost and/or activation requirement. They were designed to be more balanced or watered-down versions of the original "Pot of Greed". There are, however, exceptions to this pattern, such as "Pot of Acquisitiveness", a Quick-Play Spell Card that gives only 1 draw, as well as "Pot of Generosity", and "Pot of Duality":
"Pot of" Spell Card
Cost or condition preceeding the draw (if existing)
Shuffles 3 Pendulum monsters from the player's Graveyard and/or face-up Extra Deck into the Deck; restricts Special Summons other then Pendulum Summons.