Here is the full list of all 32 Colossus Down achievements.
You levelled the school.
You didn't kill anyone at school.
You scattered your neighbours ashes.
You scared away all the pigeons.
You made one of Donald Tank's missiles fall on an enemy.
You broke the motorbike that belongs to Kanedaaaaaaa!!!
You introduced the three passwords for access 632 without any errors.
You didn't get run down by a train on the Obsoloop underground.
You ascended the Obsotech tower without crashing into anything.
You reprogrammed GLaDYS.
You accepted GLaDYS' bribe.
You didn't smash the piñata.
You found the golden ticket.
You left the Labyrinth of Sorrow without getting lost.
You ended Angelica's dictatorship.
You crushed Kato's revolution.
You interrupted the transmission.
You found the message in a bottle.
You overcame the digital walkway without falling into the void.
You killed Gem.
You let Gem live.
You got all the questions from Ellie's test right.
You completed the Plan for the Destruction of All Things That Aren't Cool.
You left the world in Agatha's hands.
You went back in time to be with Ellie.
You destroyed absolutely everything.
You completed the mission with a broken matter recovery machine.
You destroyed 499 things.
MechaNika's core has reached level 1.
MechaNika's core has reached level 2.
MechaNika's core has reached level 3.
MechaNika's core has reached its maximum level.