I calculated the amount of xp return with both the rat traps and blood mobile, and divided that with money spent, and they were the same. others may provide better, I guess, I didn't do any others. but these will give you the most return for your time and effort. get the collider multiplier. considering how many donuts you will get in return, it's certainly worth saving you the time considering how many thousands of taps you are about to embark upon. 7 days, for 20 donuts? makes it so much quicker, it's a no brainer.
get the collider bonus and cut ur tapping down by 80%
