For formatting posts, we have these options …
You can use Markdown, BBCode, or HTML. See more discussion at: Discourse Post Format Feference Doc
We also have a custom class installed to create tables with horizontal lines (sample below), in case you don't like the default lineless style. To use it, add
<div data-theme-table="lines"> before the table html code and
</div> after it. To make table creation easier, you can auto-generate your table html code at a site like this one: Teamopolis Table Generator
We also have an extension installed to let us use spoilers. This is particularly useful for play by post campaigns.