So Many Me

You need 6 MEs wearing these 6 costumes:

Deadsamurai Dishwasher
Weapon of Choice
Lumi
Tetro Me
A.R.E.S.
Ahrah Wielder

Look at this screenshot and match them in-game when you unlock those costumes at some point:

Hi,

For this achievement you need to collect 6 unique costumes and wear them at the same time.

Here is a list of the costumes and where to find them. All of them can be found in three worlds: Outskirts, The Mine and Skyraft. I will add some videos of these world below the lists. Some of these costumes are quite tricky to get, so if you have problems getting them refer to the videos.

1. Weapon of Choice = level 2-4 (Outskirts IV)

2. A.R.E.S. helmet = level 2-7 (Outskirts VII)

3. Lumi = level 3-4 (The Mine IV)

4. Tetro ME = Level 3-7 (The Mine VII)

5. Dead Samurai = level 4-4 (Skyraft IV)

6. Ahrah Wielder = level 4-7 (Skyraft VII)



Outskirts:

The Mine

Skyraft

(video credit: Macktion)

Hope this helps :-)
Any improvements ? Plese let me know in the comments below!

Just to add to the other guides, If you are looking for a level with 6 characters, you can load up Dark Forest VI and you will automatically start with 7 Me's. Just equip the 6 costumes and the achievement should pop.
- Dead Samurai Dishwasher
- Weapon of Choice
- Lumi
- Tetro Me
- A.R.E.S. Helmet
- Ahrah Wielder

Here is a video guide, this achievement is at 39 seconds in:


Locations:
Weapon of Choice: Outskirts IV A.R.E.S.: Outskirts VII Lumi: The Mine IV Tetra Me: The Mine VII Dead Samurai Dishwasher: Skyraft IV Ahrah Wielder: Skyraft VII