Just played the save, here's the battle log:
Battlelog for turn 137:
TNT trebuchet bombards gall vetern pikeman for 1 hp.
TNT trebuchet bombards gall vetern pikeman for 1 hp. (the second pikeman)
TNT trebuchet bombards gall elite Dirty Harry for 1 hp.
TNT trebuchet bombards gall elite Invincible, shot failed.
TNT trebuchet bombards gall elite Invicinble for 1 hp.
TNT trebuchet bombards gall Josie Walls for 1 hp.
TNT trebuchet bombards elite Medevil Infantry, shot fails.
TNT trebuchet bombards elite Medevil Infantry, shot fails.
*TNT elite Immortal attacks gall elite Medevil Infantry, medevil infantry loses (Immortal has 1hp left).
*TNT vertern Greekguy the Great attacks gallic vetern ( at 3hp by bombardment) pike, immortal loses and pike is promoted to elite (at 3hp).
*TNT vetern Nasir attacks gallic vet (3hp) pike, immortal wins (3hp left)
*TNT vet BCLG the immortal attacks gall elite (3hp) pike, immortal loses (pike at 1hp)
*TNT reg immortal Urupay attacks vet gall Mad Max, immortal loses (2hp left)
*TNT reg immortal attacks gall vet Flyin' Elvis, immortal loses (2hp left)
TNT vet Immortal #2 attacks gallic elite Dirty Harry, immortal wins (1hp left)
TNT reg immortal #5 attacks gallic elite Invicinble, immortal wins (1hp left)
TNT reg immortal #6 attacks gallic elite Josie wales, immortal wins (2hp left)
TNT reg immortal #4 attacks gallic vet medevil infantry, medevil infantry wins (2hp left)
TNT vet immortal attacks vet gallic medevil infantry, medevil infantry wins (1hp left)
TNT vet immortal attacks vet gallic medevil infantry, immortal wins (1hp left)
TNT vet immortal attacks vet gallic medevil infantry, immortal wins (1hp left)
*means that a gallic trebuchet bombarded an attacking immortal. All of the attacking immortals lost 1hp.
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Overall, it was an awful RNG run. We still killed more units than we lost though, and the galls are not capable of taking Unabomb.