|| damage span
| span stands
fire se 2,0 3,-1
| span falls
fire se 2,0 -1,-1
| own span falls
fire se 2,0 0,-2
|| damage tower, loss of support, EASY_BRIDGES on
| tower stands, and supports span
fire se 2,0 6,0
| tower falls, span 3,-3 falls
| BUG: doesn't fall
fire se 2,0 1,-3