IF YOU DO NOT HAVE TRANSPARENT MATERIAL AND HOT GLUE TURN BACK NOW BECAUSE THOSE ARE REQUIRED.
Step one: Assemble the core.
Note: Red tabs on the back of the slime's eyes work like the tabs on the top of horse legs.
Note#2: The sides of the slime's mouth is intentionally smaller. In Minecraft, it may be hard to notice but it is. (THANKS GOOTUBE! :D)
Step 2: Fold the connecter piece.
Note#3: Remember, print the Outer Slime & Core piece on Transparent paper (or whatever translucent material you use).
Note#4: Fold the connecter piece in any direction, but the A needs to be facing up.
Step 3: Glue the bottom of the connector to anywhere on the inside of the outer slime.
Step 4: Assemble the rest of the outer slime, then you are done!
UPDATE 2-1-2014 7:35
Fixed the core.
Click on the papercraft design image.
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Print using your browser's Print function.