reCaptcha

The goal
I was tasked to produce a captcha GUI with a similar layout to other premium variants but with three goals: Keeping it simple, non-invasive and non-repetitive.

reCaptcha does this by only sending the GUI to players who have never completed the GUI before, hence having a reCaptcha mechanic of not resending the captcha to players who have already completed it. This decreases how annoying it is while optimizing the player base of a server as it's integration will not drive away any players.


reCaptcha provides an easy to use colour coded GUI with support for the colourblind, as it tells you exactly what colour to click on the top and the items are formatted with the correct name, making it easy to locate the correct button for anyone.


reCaptcha also logs how many times a user fails and has a configurable ban-limit, so that players who fail a configurable amount of times will be automatically banned without staff having to interfere.

reCaptcha cleverly uses the formatting for join messages provided by your server and only allows this message to send when the user joins, hence making bot attacks impossible to see for regular players.

Along with alerting staff when a user fails the captcha, it will also alert them when the player passes, this can be seen above.

reCaptcha is extremely configurable with almost everything being able to be made custom. Here is the config.yml:

captcha-times: 4 
# The time to wait in ticks before sending the GUI (20 ticks per second) 
wait-time: 4 

pass-message: "&aSuccessfully passed the captcha" 
dismissed-kick-message: "&c&lYou can not dismiss the captcha! After failing %amount% times, you will be banned." 
captcha-failed-message: "&c&lYou failed the captcha! After failing %amount% times, you will be banned." 
can-not-talk: "&cYou must complete the captcha before you use chat" 

# This is necessary to ban players after too many attempts 
Use-Logging: true 

Ban-after-too-many-tries: true 
Failure-Ban-Times: 5 
Ban-Command: "tempban %player% 1d You've failed the captcha too many times!" 

Verified-Players: 
Failed-Captcha-Attempts:

Last but not least, reCaptcha cancels events before they even happen for players who haven't completed the captcha, preventing them from moving, chatting or dying while completing the captcha,