FireWolf

Prevent trolls from joining under multiple accounts by requiring them to have verified connections, though not necessarily public. The bot can either add or remove a role on verification and this can be toggled in the web panel by users with 'manage server'.

To get in, users click on a verification link the bot posts in it's own channel, 'gateway' and authorise via Discord. Once this is done, the user gets given a role or gets rejected if they've already used a connection on the server.

There is also a choice to require a verified Steam account with more than $5 spent on it. This prevents users creating fake connections as well as new Discord accounts.

In case of a user not having any connections, an alternate means of joining the server can be used in conjunction with this bot - just add or remove the gated role and it'll be as normal.

Note that the invite URL has to be used exactly to get the bot to join the server successfully.