Runevale Idle
Runevale Idle only creates an account if you chose to sign in with Google for cloud backup. If you have never signed in, there is no account and nothing stored about you.
Settings → Cloud backup → Delete cloud backup
This permanently deletes your stored backup and your public profile straight away, removing you from every leaderboard. Your character stays on your device and you can keep playing.
One thing is kept: the record reserving your username. See "Data kept after deletion" below for what that is and how to have it removed too.
If you cannot open the game — you uninstalled it, lost the device, or cannot sign in — email runevale.support@gmail.com.
Use the subject line Account deletion and send it from the Google account you signed in with, so the request can be matched to the right data.
An emailed request removes everything, including the username reservation that the in-game deletion keeps. Say so in the message if you specifically want your username released as well.
Requests are handled within 30 days.
Everything is deleted permanently. No backup copy is retained afterwards and it cannot be recovered, so export your save first if you want to keep it: Settings → Save data → Export save to file.
The character stored on your own device. Deleting your account removes the copy held on the server only. To remove the local one as well, uninstall the game or use Settings → Reset progress.
If you deleted from inside the game, one record is deliberately kept: the entry reserving your username, which holds your account identifier and nothing else. It contains no game data, no email address, and nothing about what you did in the game.
It is kept so that nobody can claim a name you were known by on the leaderboards and be mistaken for you, and so that the name is still yours if you come back.
If you want that removed as well, email runevale.support@gmail.com and ask. Once it is removed the username becomes available for anyone else to take.
An emailed account deletion removes everything, including this record. Nothing at all is retained afterwards.
If you reported another player, that report contains your account identifier so it can be reviewed. Reports are removed with your account when you request deletion by email.