Board Game Arena

When creating a table there is an option "undo moves" (I use the site in my language, so perhaps the wording is different).

a) How to undo a move?
b) Why are there 3 options: "off", "on", "on, even if it disturbs the game's balance"?

This is a standard option for games created with BGA sandbox.

a) there is a "circle back" arrow on the right of the status bar (in turn based, I noticed it overlaps with the next table arrow, it's a small glitch to fix)
b) "on" means undo after a game action except after actions triggering a random event or actions revealing secret information; "on even if it disturbs the game balance" allows undo after any game action.

In practice, most games are created using the classic studio and not the sandbox, so this applies to very few games (and may not be perfect).

Thanks for the explanation. Then I could not have noticed the arrow as I have played this game turn based.