Acquire the Bow of Apollo

Ride over 100 miles.

Finish a race within 0.1 second of another rider.

Do a wheelie lasting at least 500 feet on a motorbike.

Defeat 50 enemies with stealth attacks

Defeat 30 enemies with the Wes - 44

Finish the game in Easy Mode

Defeat 100 enemies with headshots

Defeat 20 enemies with a single punch, after softening them up with gunfire

Find 20 treasures

Find ten treasures

Defeat 50 enemies with hand-to-hand combat