Addiction should never be the goal. Addiction is "a compulsive dependency" and is not an ethical design goal. At the end of the day, you need to offer real value, or people will burn out and won't stick around for long. This is why so many games are engaging for a while but then lose steam. Read my book, Hooked: How to Build Habit-Forming Products, to learn how to build engaging products the right way.

Dopamine is not the only thing.

You may want to focus on adrenal gland failure too if you can mix "-Constant positive.......bright colors" into a 5 minute window :p

https://www.healthline.com/health/dopamine-addiction

Story that gets you involved with characters.

I think how depressed I was when I got to the bad end of Megadimension Neptunia VII, I quit playing for 24 hours but then jumped right back in.

don't