One of my favorite things about discord over IRC is the use of in-line emoji. A lot of cool emoji come with standard Unicode now, but you can make even more and upload them to your own server! And, you can use (if server admins allow it) them on other servers too!
Here's some default unicode emoji: Cowboy, and "pensive" face (sorry they're huge: these are SVGs and the forums will just scale them up as big as they can go! I don't know how to make them smaller!)
(https://discord.com/assets/c18f8f63a3232a0d246868b4d9f20f7b.svg)
(https://discord.com/assets/2ea1f6bba4448fa4e8d9504fe976095d.svg)
A common theme is combining cowboys with other unicode facial expressions. To make the cowboy sad, cool, shocked, etc
(https://cdn.discordapp.com/emojis/755647873307377778.png?v=1)
(https://cdn.discordapp.com/emojis/772637877359083550.png?v=1)
(https://cdn.discordapp.com/emojis/772637877325529118.png?v=1)
Discord emoji also support animation
(https://cdn.discordapp.com/emojis/658548051857899551.gif?v=1)
Here are two I just made. Autism punisher skull (the puzzle pieces mean autism)
(https://cdn.discordapp.com/emojis/848587488174931969.png?v=1)
And, sad punisher autism cowboy.
(https://cdn.discordapp.com/emojis/848587258864992268.png?v=1)
Here's one I made a long time ago. Cuddly penis.
(https://cdn.discordapp.com/emojis/645391266720251930.png?v=1)
Here are some of my favorites that other people have made
Yeecaw
(https://cdn.discordapp.com/emojis/755647873663631470.png?v=1)
Yeeclaw
(https://cdn.discordapp.com/emojis/755647873713963058.png?v=1)
Yee.. turtle
(https://cdn.discordapp.com/emojis/755647797591670874.png?v=1)
Negative man
(https://cdn.discordapp.com/emojis/725540928059736095.png?v=1)
Whalecum
(https://cdn.discordapp.com/emojis/609779779633283072.png?v=1)