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Sleep as Android has this along with a ton of other wake up helpers like QRcode/NFC tag scanning to stop the alarm, math problems, etc.

I found the math worked well at first but I apparently got too good at solving them in my sleep.

I put an NFC tag in the bathroom which requires me to get out of bed and go into the bathroom to stop the alarm. That's usually enough to get me to stay up

They also have various CAPTCHA tests, one that requires you to hold your phone and spin around, one that requires you to put the phone up to a light source, and other such things. I'm sure you can find an effective solution that works for you