Here is the full list of all 27 Max: The Curse of Brotherhood achievements.
You defeated Mustacho and saved your brother!
You defeated Mustacho without dying even once!
No Evil is safe from you and your Grabby Hands.
You found and assembled the entire Amulet for the Old Lady!
You didn't die in Death By Lava.
You stole back your kid brother like a boss!
You lit 15 enemies on fire. Oh the things One does for brotherly love.
It's all in the fingers and fiery balls of death.
You drew 200 water streams.
You destroyed 50 of Mustacho's Evil Eyes. His control is diminishing!
You found and assembled 12 pieces of the lost Amulet.
You escaped the Beast without dying!
You drew 200 vines.
You drew 200 branches.
You destroyed 25 of Mustacho's Evil Eyes. Consider his surveillance network impaired.
You found and assembled 6 pieces of the lost Amulet.
What goes around, comes around. Right in your face.
One Sea of Sand, 2 Earth Pillars, 3 drawings - piece of cake.
Up you go.
Time Marches On. (Rang a bell)
Can't Touch This
You tamed the Spikester! ...Lucky you.
Guts and Glory
You found the first piece of the lost Amulet.
You destroyed 5 of Mustacho's Evil Eyes. That'll teach him.
You used the magic marker 25 times.
And just in time for tea! (Reached the old lady in under 5 minutes)