Some pretty important advice

[GamingGuyTyler]

Do not ever, ever, put in other mods in already existing modpacks. Recently I tried playing Tekkit on my laptop. I decided to try and put optifine in to reduce some lag. It didn't work that well, but it still worked nevertheless. Then, I started seeing..weird things. I went to my inventory and saw my skin like this: http://prnt.sc/b6vels and I have no idea why. I played a bit more and I got tired, so I decided to close the game. When I was about to quit minecraft, I saw a bunch of images of the same thing just randomly placed. Sadly, you can't screenshot at the main menu, but I think that's for the best. Anyway, lesson learned: NEVER PLACE MODS IN OTHER MODPACKS THAT AREN'T YOURS.

Edited May 21, 2016 by GamingGuyTyler
accidentally made a little typo

[Melfice]

Alternatively: DO put mods in existing modpacks.

This seems like an odd error, but probably all due to Optifine. Did you have the right version? Did you have it installed properly? Were there settings you could have altered?

[JaariAtmc]

Alternatively: Do not put mods in other modpacks that aren't yours, UNLESS you know what you are doing.

[Melfice]

20 minutes ago, JaariAtmc said:

Alternatively: Do not put mods in other modpacks that aren't yours, UNLESS you know what you are doing.

That too.