Here is the full list of all 44 Nefarious achievements.
Beat the game having collected less than 1,000 lucre.
Beat the game without buying a single upgrade.
Honored the terms of your dark pact with Kaptain Man.
Defeat Guryon in Winterdown without getting hit once.
Beat Dash in Insektia without taking any damage.
Hit the swat van with one of it's own bazooka blasts.
Achieve S-Ranks on all stages.
Beat Dash, Guryon and the 8-bit heroes without dying or taking damage at the Bramble Flats.
Complete Rattletrack Rails without dying.
Buy every upgrade in the upgrade shop.
Unlock all upgrades, view all endings, find all the vinyls, and collect all the crowns in the game.
Listened to the heroes entire motivational speech at Bramble flats.
Find all the crowns in the game.
Unlock all the music for the Jukebox.
Defeat Mack at Adept Co. without getting hit once.
Get the bad ending.
Sacrificed friendship to achieve your cruel ambitions.
Beat any stage by only punching, without firing a single long ranged weapon.
Defeat Mechano using only his own missiles.
Get the good ending.
Put your friendships before your ambitions.
Drop the kingdom's assembled defenders into the lava pool at Crow's Fortress in Bramble Flats.
Witness the might and fury of Monster-Farrah.
Had a long conversation with your upgrade station S.T.A.B.I.L.E
Witness Dr.Cackle being arrested.
Tell Mayapple not to drop Dr. Cackle in his Lab.
You have appeared on the dating game "Would You Date a Super Villain?"
Have the audience choose Crow to date Becky in "Would You Date A Supervillain?"
Unlock Farrah's Folly.
Find all three mutant Farrah Days
Read all 16 terminals in Adept Co. and discover who funded the sinister organization.
Defeat the Treble Rangers at the Villain Museum.
Read all of the portrait descriptions of Crow's Lineage in his wing at the Villain Museum.
Found the hidden monster at the villain museum.
See all the dialogue scenes in Heartless Abyss.
Counting any amount spent, gather a grand total of 10,000 lucre.
Defeat 100 enemies with punches.
Defeat 100 enemies with grenades.
Get the first crown in Sukochi.
Defeat 50 enemies with grenades.
Defeat 50 enemies with punches.
Defeat 20 enemies with grenades.
As a result of being defeated, dropped a princess.
Defeat 20 enemies with punches.