Here is the full list of all 29 Sydney Hunter and the Curse of the Mayan achievements.
Completed the game with good ending.
Defeated the Sun Deity
Defeated Kukulkan human form
Defeated all gods during the boss rush
Collected Kukulkan's key
Defeated the Lava Idol
Defeated the Death Deity
Fully upgraded your whip
Defeated the Rain Deity
Acquired the sun block from Anna
Defeated Kukulkan in serpent form
Acquired the mask relic
Collected Gems 867-5309
Defeated the Maize Deity
Defeated the Bee Deity
Collected the Boomerang
Purchase first Maya Meal
Collected the Spear
Defeated the Jaguar Deity
Killed 25 bats in any level
Killed first ghost
Kill 1st snake
Statue Save Game Checkpoint used for first time
Everyone gets a participation trophy
Collected all Yellow Diamonds
Yuki gets her lost HuCard
Found all treasures in Shrines of Peril Arcade Game
Found all Crystal Skulls
Sydney on Ice. Bad Ending