Disney Epic Mickey 2: The Power of Two

This is Blot Alley Superstar - Befriended the Blotworx and helped Petetronic. At the end of Blot Alley you have to wait for the door to open and fight 3 enemies. To get the achievement you can't kill them. To get the cars you have to punch off their fronts with X to expose the red button. Once you do, jump on it and spray the blot with paint (RT). Do the same for the other one and the other guy (jump on the button and paint).

To be safe, do the friendly route (not killing any blots in Blot Alley). I didn't and still got it, but Fancy Bacon only got it by doing the friendly way.

Up Johnny had done the friendly route and dd not get the achievement. So, I'm saying this is glitched and keep trying. Perhaps you could copy a save to a thumb drive before going to see Petetronic so that if doesn't work, you can keep trying until you get it.

Throw out the TV sketch as soon as the encounter starts.
Run to the enemy on the right, his grill, jump on the button on his head, then paint him.
Immediately throw out the Watch to slow time.
Jump on the central robot's button on his head and then paint him.
Run to the left enemy, his grill, jump on the button on his head, then paint him.

If any of the enemies explode, immediately pause and quit to title, then continue to try again.

These are steps I followed in order to get the achievement.
1) Make a backup of the save at the beginning of Blot Alley. (e.g. flash drive usb; I used the main save on usb and backup on the HDD)
2) You don't have to use thinner.
You can jump over the already half-thinned wall (try on the lowest crack) on the left without use the thinner in order to reach the trapped gremlin.
3) Save the trapped gremlin, go back to the start position (by jumping the half thinned wall again) and go through the level step by step, one by one (no need to rush at all) painting all the blots without them ringing the bell.
There are 3 sub-areas in the path to Club 13, take your time and watch the enemy moves before painting them.
If you run out of paint, just press "X" on the lamppost or on the tables in the area (befriend the fat blots from distance one at a time and refill paint as I previously said). Go for a stealth playthrough (get invisible by bathing in the wells situated at the beginning of each sub area - paint the flowers near the wells in order to fill up them with invisible paint) and always aim for one enemy at a time
4) In the last part (before Ian's cutscene) there are 2 small blots to befriend (besides the ground ones - 1 small + 2 fat blots - remember the "one at a time" rule) in the first floor of 2 opposite buildings; start from the springboard trashcan, jump on, get the one on the right and follow the path to the left by jumping from the shelves, get the second one and head to the big door by walking straight (without using fireworks on the ground floor to open an access). If you have done right Ian will tell you and give the pin and continue reading the list, otherwise you have to start again Blot Alley. (copy the backup save to your actual save location, load it and start from point "3")
5) Overwrite backup save with the club 13 checkpoint BEFORE ringing the doorbell.
6) Once the last fight is started, first go for the front of each car by pressing "x".
Keep in mind to group the enemies (by walking in small circles) in a limited area so you can save time moving from one to another.
7) Start befriend one of the cars by jumping on the red button exposed and spray with paint the blot inside.
8) As you befriend the first one, IMMEDIATELY use the clock sketch and go for the second car quickly.
9) Befriend the last one (jump in the head within the last seconds left from the clock sketch lenght so you are safe ) and you have finished.
IF YOU FAIL (blotworx destroyed by your hand or not), exit quickly and reload.