Here is the full list of all 36 Trillion: God of Destruction achievements.
Watched the true ending!
Affection Points have surpassed 1 billion!
Used every Death Skill!
Defeated Trillion in its Final Form!
Defeated Trillion in its Dragon Form!
Strengthened a weapon by +30!
Amassed a variety of Active Skills!
Opened up all the Demon Seal slots!
Defeated Mokujin with one hit!
Began a second playthrough!
Defeated Trillion in its Titan Form!
Inflicted 10 billion damage with one hit!
Used Order for the first time!
Reached the MAX level in a relationship!
Amassed a variety of Passive Skills!
Gave someone the best present ever!
Strengthened a weapon by +10!
Executed Double-Up for the first time!
Got 100,000G!
Completed all entries in the Gift Guide!
Retreated for the first time!
Unlocked "Holy Illusion"!
Broke through Trillion's outer armor!
Executed Fever Time for the first time!
Leveled up a skill to the max!
Used Interact for the first time!
Challenged the Valley of Swords for the first time!
Performed a stat increase for the first time!
Gave a present for the first time!
Powered up a weapon or opened up a slot!
Trained for the first time!
Obtained every trophy!
Watched all the lovey-dovey endings!
Defeated Trillion with one of the first three Overlords!
Cleared Challenge Mode!
Watched everyone's hot springs event scenes!