Welcome to Rockmosis' Developer Blog/Forum #1.
This will be my little place to announce changes and take suggestions to the format of this wikia.
Spoiler tags have been added to hide walls of text or spoilers under a collapsed table. The bit to use it is {{spoiler|your text here}}. You can do your normal paragraph spacing and other stuff within the spoiler tag, just remember to end it with the }}.
It works in source editor and default editor, but not in the new visual editor. But that's not too big of a problem because comments don't use the new visual editor and instead use the default editor. It will only be a problem if you put it into the actual page, but spoiler tags usually aren't used there.
TLDR: Use {{spoiler|your text here}} when you're spoiling something in comments.