Shadow Warrior (1997) Sprite
In the area across from Wang Cave, near the stairs that lead to the mechanic’s location, you can double jump to a ledge, and then double jump to another ledge that contains a holographic sprite from the original 1997 Shadow Warrior.
Dwarf Fortress reference
During the Hot Blooded mission, you can find a cave that includes graffiti of faces and the message “DF is real.” This is believed to be a reference to Dwarf Fortress.
Flying Wild Hog logo
Larry’s jacket features the logo for Flying Wild Hog, the game’s developer.
In the Wang Cave bar, go to the stage with the empty drum set on it and head to the right. There is a locked door, but you can pass straight through it into a secret area devoted to the developers, including a large picture of the development team.
Batman and Wonder Woman
The bathroom door in Wang Cave is labeled with an image of Batman for men and Wonder Woman for women.
During the mission Ninja’d Scrolls – Part 2, you can find a hidden passage behind a wooden wall in the cave where you find the guard with the key to Dojo Kid’s cage. Cross through the passage and destroy the walls to find a secret room filled with Minecraft blocks.
Harry Potter cave
One cave includes an area that strongly resembles the cave where one of Voldemort’s Horcruxes is hidden in Harry Potter and the Half-Blood Prince. It even includes a bowl and a wand, further referencing the Harry Potter cave.