Here is the full list of all 20 ZHP: Unlosing Ranger vs. Darkdeath Evilman achievements.
Use emergency morphing once.
Overcome a trauma.
Die 50 times.
Kill 100 Metal Cacti.
Complete the Nippon Ichi: Netherworld Wars dungeon.
Synthesize a piece of equipment to +99.
Unlock all costumes.
Clear Mastery Cave: Absolute Hero Level.
Defeat the Final Last Boss (save Darkdeath and the world).
Unlock all territories in the Shadowgram.
Reach level 9999 inside any dungeon.
Reach a total level of 999999.
Complete the Character Book (all ranks).
Complete the Item Book.
Purchase all tunes from the Music Store.
Allow your Home to fall into disrepair.
Deposit 10,000,000 WP in living expenses.
Defeat Darkdeath Evilman in the opening cutscene.
Obtain all pieces of the Giga Darkdeath Evilman set.
Achieve all achievements.