Here's how they work:
Slime stops viruses and ties.
Shell stops -6 shots and Venom
Poison stops -1 shots and info shots (those + shots, like Icarus's Turning shot)
You can make a shot more powerful by storing a positive value in .shootval for -1 and -6 shots. This number is what multiple of the cost for a shot you're spending. The shot increases roughly log base 2 (energy spent) * 100 percent.
You can make shots have a further range as well. Store a negative number in .shootval. This number is what multple of the cost to shoot you're spending. The shot increases roughly log base 2 (energy spent) * 100 percent.
