since in my guild we're using Discord to arrange trials and since it was very annoying to make long messages with trial rosters and even more to edit them each and every time a user wants to join in/out I created a bot that does the job for you.
Given these 3 informations:
Trial Name (in shorthand like vaa or vss)
Trial Date (in any format as long as not containing the "-" symbol)
Trial Time (in any format as long as not containing the "-" symbol)
Noldobot will create an interactive message looking like this:
The actual required roster will change accordingly to the specified trial (here it was VSS requiring 2 tanks, 2 healers, 5 DDs and 3 runners for portals) and the bot will add reaction-roles to allow users to join in.
Users will be able to join the trial by pressing the desired role and the bot will update the message just like this (here I'm joining as magDD):
More detailed information about usage and the link to invite the bot in your own server can be found on Noldobot Website
For any further information that you don't find on the website feel free to ask here