I think the extra strikes is bugged. It's supposed to allow you to get an extra X every time you buy the upgrade.
I looked in the script and saw the issue - the strikes upgrade is adding to how many strikes she starts with. So if you purchase the upgrade twice, she starts with 2 strikes and needs 2 +3 strikes to game over, making the upgrade pointless.
So that's what happened. I was wondering where did I get all those strikes!
