I'm sure it's been posted elsewhere, but I am too lazy to look that deep. but here are a few I know.
1. Doppelgangster is a pun on Doppelganger which means a look alike or body double.
2. Harrison Jones is obviously a nod to Harrison Ford and his iconic character and treasure hunter Indiana Jones.
3. Finkle Einhorn is a reference to the movie Ace Ventura: Pet Detective.
4. Sleepy Dragon is most likely a reference to The Hobbit and the treasure protecting dragon, Smaug.
5. Bloodworm's reference is to a leech. Which sucks blood from its prey to live. which is why it has lifesteal.
6. Dinosize's flavor text refers to the former practice of Supersizing a meal at Mcdonald's.
7. Kobold Monk's flavor text refers to The Matrix in which the young child under the supervision of the Oracle tells Neo, "there is no spoon."
8. Zola the Gorgon's flavor text and name refer to gorgonzola cheese.
9. Branching Path's flavor text refers to The Road Not Taken by Robert Frost.
Possibles:
1. Arfus's art looks like it was drawn in the style of a Patronus from the Harry Potter series.
2. Drain Soul looks like a reference to the Mortal Kombat series.
2