19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...

The goal is to be the last player standing. A configuration page allows you to enable/disable arithmetic operations (addition, subtraction, multiplication, division), 2 digit numbers and exponentials.