Play button ERROR

[Mine_Craft_DJ]

I, press play then it loads in all that other stuff down below. Then my cursor has the loading thing then it goes back to launcher. Please help trying to play Pixelmon.

[Torezu]

No logs means you're unlikely to get any help.  Crash to Launcher is very common with version/block_ID/item_ID/server-client/etc mismatches.