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