So, orcs just aren't cutting it for an advanced fortress. Even they can be made to break and run.
Is there a way to mod them to a) send really, really huge siege groups that b) don't break or leave, and preferably, c) will stay until the next siege group arrives?
As far as i researched, sieges have the hardcoded limit (maybe +-, but i'm sure because that's my statistic):
1. Not more than 16 warriors in a siege group. (And rarely less than 16)
2. Total number of sieging groups not more than less of ([PROGRESS_TRIGGER_POPULATION] tag and [your site population in tens]).
Different civs can siege you together at one time from differents corners.
So once i have a siege of 7 groups (4 orxz and 2 orcs and 1 human) that ended with total 113 corpses.
There were only 18 dwarves that struggles bravely but they were hopeless outnumbered, so i lose the fort.
*Attention*
The fort was situated in evil mountains with a view onto haunted swamps, have three enemies (orcs+orxz and goblins) in upper lines at embark point.
Orcs have:
[PROGRESS_TRIGGER_POPULATION:2]
[PROGRESS_TRIGGER_PRODUCTION:6]
[PROGRESS_TRIGGER_TRADE:5]
Orxz have:
[PROGRESS_TRIGGER_POPULATION:5]
[PROGRESS_TRIGGER_PRODUCTION:10]
[PROGRESS_TRIGGER_TRADE:15]
Humans have defaults, and they come into attack only when other groups were almost defeated and almost every dwarf had red-grey-brown wounds.