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