The Toothbrush Mustache Draw Source lets you draw even deeper.
RD/MRP1-JP034 プログレス・ポッター Progress Potter
Level 3 WIND Psychic Effect Monster
[REQUIREMENT] You can activate this by shuffling 5 monsters from your GY back into the Deck.
[EFFECT] Choose up to 2 cards in your opponent’s GY and shuffle them back into the Deck. Then, you can draw cards equal to [the number of different card names of “Progress Potter” and “Pot of Avarice” in your GY].
Basically any Progress Potters in your GY, draw 1. Any Pot of Avarice in your GY, draw 1. Have Pot of Avarice and any non-zero number of Progress Potters in your GY, draw 2.