These are a list of glitches or former glitches.
hello kevin Reaction fail
hello kevin Reaction Fail is a glitch when you use the secret command hello kevin and add a reaction, causing the message sent to hit maximum reaction. Following this, 67 Kid will say 'Failed to add [EMOJI] emoji!'.
42067
Because of how 67 Kid works, an oversight is that commands can be paired together with 67. How it works is that 67 Kid searches through each letter A-Z and each number 0-9 if it contains 67, but also for other commands, meaning it can say each command. This includes a double 67. These are known as the 42067 technique and is used for efficiency on the Row streaks leaderboard.
Failed to add reactions
If you spam a reaction-based command too much (67, 67!, 67?, 420, my moms kinda homeless), it can fail to add the reaction, prompting an error message. One case of this has happened. [1]