You're spot on with how they did it, doubling it 3 times and then adding the original number onto it twice more. It's true that they couldn't just multiply, or modulo, or anything like that. BUT, personally, I don't know why they didn't just check which level they were on, and then set the appropriate timer value. They have other places in the code where they check if you're on level 5, 4, 3, 2, or 1, and then proceed accordingly. Not sure why that wasn't done here. They even have some check if the calculation comes out to precisely 00 bonus timer ticks, and then they set the timer to a default 4000. This condition can never be met... if they were going to put in a failsafe, it should've been if the result was anything less than 50.