This hack removes color emphasis bits at PPUMASK $2001, which was used in this game, making picture bright and colorful as it should be.
Database match: Cliffhanger (USA)
Database: No-Intro: Nintendo Entertainment System (v. 20210216-231042)
File SHA-1: F7F697344FF0251A8DE88E39BE23913C2D8D8F53
File CRC32: 7D51A6DC
ROM SHA-1: BE56DF3A7FA18ED2C6B1C5EE991866916373FC3C
ROM CRC32: 57C2AE4E