Here is the full list of all 43 Millennium 4 - there are Beyond Sunset achievements.
Hard Mode Completed
Finish the game in less than 13 hours in Hard Mode
Kill 1000+ enemies with The Bear
Kill more than 1000 enemies with Bokden
1000+ fights
Held more than 99,000 Gold
Complete the game fully (all quests, secret rooms and animal kings)
All secret rooms found
All quests completed
Spend 40+ hours on the game
Kill Urchin Nation
Kill Shooking
Complete Q9 (Find Jacque's Hair Potion)
20+ secret rooms found
Kill Perfect Chopper
Kill all animal kings
600+ hits with Salome's Hands
Kill Gorilla Lord
3+ hits with James' Hands
Kill Kingdom of Weapons
Kill Legendary Warrior
Kill Soil of War
150+ items found
Defeat the Tyranosaurus
Find 40+ XP baskets
Register Old Suzuki (just in time!)
Find 5+ secret rooms
Pass the Crystals trial
Convince the Bear to join
Kill 15+ groups of Tianas during the second trial
Go through the Grand Rift
Kill the King
Recruit Wolfgang
Kill Golem Overking
99+ hits with Bokden's Hands
Complete 6+ quests
Recruit Bokden
400+ hits with Marine's hands
Get 50+ Gold from a gold sack
Find 1 secret room
Complete 1 quest
Play 1+ hour
Reach lvl 6 in Bare Hands with Benoit