How to get actual time, not system time

Question

If I want a timer in a game that is not impacted by a user changing their OS clock, how might this be done? For example, if I wanted to know the time in real life that has elapsed since an action was performed in hours or days. If I pull time information from the user's OS, then the user can adjust their clock as a "hack". This is something I would like to avoid incentivizing.

Answer 1

If you want to get time without using the OS, then I guess the only way would be to do an HTTP request to some server you trust in order to get that date.
Maybe websites like https://time.is/ have an API to do this?

However that would be a bit lame for a game to do that if it initially doesn't need internet connection (aka not multiplayer/no remote ads/whatever online)

Answer 2

Well if you dont want to use os clock the only other way i could think to do this is to make your own clock in game utilizing delta in fixedprocess(). delta is the time between rendered frames.