Screamers are spawned when the Heat Map % hits 100 (the number then resets to zero and starts over). Each forge, campfire, and anything else burning wood (chem station) adds 1.5% immediately, then gradually adds 1.5% per fire per minute. Auger and chainsaw didn't raise the percentage at all, despite holding it and running it against various blocks (exception, hitting the chem station with the auger added 0.5% total, for some reason). Shooting, punching, burning barrels, and torches...nothing else seemed to. Odd, since in b197 running the auger at bedrock for even a minute or two would draw screamers in.
In the past we have been told that tools, gunfire, and ever farting from the chili would raise it (brief: in A12 when smell still worked, I was carrying 55 meat, alot at the time, and drew screamers just standing around doing nothing). Conclusion, the fires are predictable, everything else seems to be either random, not measured properly, or broken.
