Open the codes menu
Tap the Codes button in the top right of the lobby. Some codes require you to reach a specific wave first, so check the requirement before redeeming.
Paste exact text
Codes are case-sensitive. Most include a trailing exclamation mark. Use the Copy Code button on this wiki to avoid typos.
Claim before event ends
Event codes often expire without warning. Redeem the no-lock codes (CRAFTNERF!, JJKUPDATE, BURAH) before any progression-locked codes (67CODE!, SRYFORSHUTDOWN!, BLEACHPART2!).