Here is the full list of all 50 Ultra Savage achievements.
Reach Level 200
Defeat Dr. Congo
Enhanced Item +20
Have Over 10'000'000 HP
Defeat Unlimited Nightmare Error
Defeat Unlimited Error
Defeat Error
Reach Level 180
Defeat Oreb and Zeeb
Reach Level 160
Defeat Githeon The Galactic Conqueror
Reach Level 140
Do Ten Time Travels
Made A Costume
Enhanced Item +10
Defeat Xoreb
Defeat Nahash
Deal Over 10'000'000 Damage
Do Six Time Travels
Have Over 1'000'000 HP
Reach Level 100
Defeat King Bera the Reaper
Reach Level 80
Have Over 100,000 HP
Defeat Lord Pretty Face Coolinagi
Enhanced Item +6
Do Your Second Time Travel
Defeat Raki-Raki The Demolisher
Deal Over 1'000'000 Damage
Reach Level 60
Have Over 300% ATK SPD
Do Your First Time Travel
Deal Over 100'000 Damage
Defeat Liki Lee The Amgi-Turner
Deal Over 9'000 Damage
Have Over 50% CRIT
Enhanced Item +3
Defeat Heli Boss
Have Over 100 CHI
Maxed Out A Skill
Deal Over 1'00 Damage
Reach Fusion Level 10
Reach Level 30
Have Over 150% ATK SPD
Defeat Prince of Madness
First Enhancement
Equip a blade and meet Kairon
Reach Level 10
Have over 3'00 HP
Do your first fusion