If you’re a gamer who loves the Super Mario Bros. series, but have already finished all the games, there’s only two options: build your own levels or play custom levels created by others. Continue reading to see ten of the coolest fan-made Mario levels and modifications.

1. Half-Life Bros

2. Frustration

3. Super Mario Crossover

4. LittleBigPlanet Mario

5. A-Hole Castle

6. Green Hill Zone (Sonic-inspired)

7. Unreal Tournament Mario

8. Street Fighter Mario

9. First Person Mario

10. Mario Meets Doom