A way to challenge yourself if the default game does not do that is modding on how to increase the odd of losing by making the game harder in opposition of increasing the odd of losing by giving your fort self-handicaps (make no wall, no trap, don't train military too much, embark near those overpowered undead tower, evil terrifying surrounding embark etc..)
Code wise, i think the "losing is fun" will really happen once Toady will get to his military dev plan
www.bay12games.com/dwarves/dev.html( scroll down to Improved Sieges )
And as invaders can be turned off, everyone still win, the guys that want martial challenge and the guys that want to oversee their fortress without the war side being a threat or denaturing their map with digging.
Anyways, some modding ideas you can easily implement
- make every animals and every non-dwarves creatures willing and wanting to murder your dwarves in a "Boatmurdered" atmosphere .
This can be done by adding
[CRAZED]
[NOFEAR]
to every creature definitions in the raws , just don't add [CRAZED] to your dwarves or you'll not be able to play a fortress (game would end immediately after embark), take time, but when you're going to see a bunch of previously harmless and pacifist groundhogs suddenly rushing toward your fortress with murder intent, it's hilariously worth it.
You're not going to look at those things moving around your map with the same eyes.
- Add many variants/clones of the goblin entity from the entity_default.txt , this would help to make more enemies to your civilisation, making your fortress being sieged much more, in order to not give you much room to breath and put then some pressure on you.
- Give your enemies the ability to siege you (much) earlier by editing the entity_default.txt for the dwarven entry, change
So according to this, to increase the challenge against gob siege, you may want to change
[PROGRESS_TRIGGER_POP_SIEGE:3]
[PROGRESS_TRIGGER_PROD_SIEGE:0]
[PROGRESS_TRIGGER_TRADE_SIEGE:0]
into
[PROGRESS_TRIGGER_POP_SIEGE:1]
[PROGRESS_TRIGGER_PROD_SIEGE:1]
[PROGRESS_TRIGGER_TRADE_SIEGE:1]
So gobs may be willing to siege when
- you reach 20 pop
- or you reach 5000¤ of created wealth
- or you reach 500¤ of exported wealth
instead of being willing to siege only when you reach 80pop (+/- somewhere near year 3 of your fortress)
There are certainly much more modding possibility to improve the difficulty for your own fortress fun.
That or go look for mods like the fortress defense one.
Now there's the problem of walls, despite climbing is a feature, siegers will not climb the majority of time, so turtling in will still defeat every siege attempt, nothing much can be done there without handicaping yourself with holes in wall and etc ...