Quicky Fortress/Small Castle Generator

Initial Profile (What the PCs see when they first roll up)

-# Of Outer Towers: d12

-For landlocked forts, assume it's symmetrical or pick a shape. Each tower has d4 defenders visible.

-For seafront forts...
Troops and shape: roll a number of d6s equal to the number of outer towers. Where each die lands shows the location of a tower relative to the others. What's on each die shows the number of troops visible in each tower. Drawing a line "connecting the dots" from one die to the next shows the shape of the fortress and (roughly) the stretch of coastline it defends. Assume the landward side is wherever the largest gap between dice appears. There's a picture down there if you're confused. For scale, imagine each die represents a tower 20' across.

-Outer Walls

The walls'll be 3d20 feet tall, and the towers'll be d20 feet above the walls.

For seafront forts: Generally below the walls there's 2d20 feet of sloping ground. This is (roll d4) 1-normal 2-muddy and slow-going 3 muddy and slippery 4-rocky and slippery.

-Ease of climbing depends on the age and tech level of the fortress, roll d10 and subtract 5. A negative number means a corresponding minus to climbing checks, a positive number means a plus. Assume a climb speed of dex divided by two feet without a rope or dex feet per round with one unless you've got another system.

Defense profile (What you have to deal with if you're trying to get in)

-The total population of available defenders = number of defenders visible x d20
d4 will arrive per round in case of alarm

-Outer Defenses

The initial volley from the towers in case of an unexpected attack will be standard bow or crossbow fire.
The second volley in case of a siege, an anticipated attack, or a small but persistent raiding party (like a bunch of PCs) will be as follows:

(d4 normally) (d12 for a goblin fortress)
1 More standard bowfire
2 Flaming arrows/bolts
3 Poisoned arrows/bolts
4 Boiling oil (-3 to hit, d6+3 damage)
5 Green slime vats
6 d4 Pig balloon riders
7 d4 Othuagg babboons (per tower)
8 Floating, biting, gas-spore like beings w/hallucinogenic spores
9 Goblin witch
10 Goblin alchemist w/ d4 weird devices
11 Goblin maggot priest
12 d4 Eyes of fate (per tower)

-Gatehouse ("Front door") Defenses

Roll 8 times on this table, rolling the same result twice means that roll's "wasted":

1-Barbican or gatehouse is up a winding staircase 4d20 feet high
2-Moat (d6+4) x 10 feet across (25% w/monster) (25% curving causeway (2d100 feet long) through moat (allowing more arrowfire as foes cross)(25% full of acid)(25% hallucinogenic fumes)
3-Inner portcullises cut off gatehouse at both ends
4-Arrow slits in gatehouse
5-Murder holes in gatehouse
6-Barbican with murder holes and arrow slits in front of gatehouse (50% has roof) (50% has cut-off portcullis)
7-Secondary walls--d20' higher than outer walls, # of inner towers = number of outer towers minus d4
8- Exotic monster let loose in barbican (or gatehouse if there's no barbican) in case of attack

-Lowest windows (in case intruders are trying to grapple and climb in them) will be d20 + 30' up. They can be treated as AC 15 +d4 or AC 5 - d4 for purposes of trying to chuck a grappling hook up there.

Complications (d4 of these)--Roll d30 d4 times per fortress to decide which

1-Secret entrance. Roll a d12, this represents what "o'clock" the secret entrance is at, assuming north is 12 o'clock.
2-Fortress garrison is being attacked by local faction when PCs arrive
3-Fortress garrison is being attacked by a monster when PCs arrive
4-Fortress garrison is dealing werewolf/changeling/The Thing, other "enemy-within" type monster when PCs arrive
5-Fortress garrison is lazy drunken debaucherous irresponsible louts
6-Crazy dangerous beast is being transported to the capital and being housed here in the meantime
7-Mad treasure kept below: d10x100 gp worth
8-Mad crazy treasure kept below: d6 x 1000 gp worth
9-Interesting treasure kept below: d10x100gp worth plus one magic item
10-Internecine warfare within garrison
11-Garrison has horrible disease
12-Important prisoners kept in the dungeon
13-Bizarre architecture. Fortress is built on stilts, struts and pillars
14-Bizarre architecture. Fortress is built of some bizarre semitranslucent stone--shadows move and wells of torchlight flicker within
15-Bizarre architecture. Fortress partially made of colossal animal skeleton
16-Bizarre architecture. (Other.)
17-Poisonous or carnivorous mold, vines, algae covering everything. Garrison protects itself with bizarre filter masks or injections.
18-Crazy wizard's lab experimenting within
19-Important visitors--lords or ladies or something
20-Weird chaos cult or demon worship
21-Recent natural disaster has created a crack in the castle's defenses
22-Garrison's expecting people and think the PCs are them
23-The fortress's garrison is rebelling agains the lords that nominally control it. May attempt to enlist the PCs to their cause
24-A feast or somesuchlike is being celebrated when PCs arrive. Garrison's probably distracted
25-The garrison is cursed. Hollow-eyed and hopeless
26-Princess locked up in tower needs to be rescued.
27-A desolate area. Garrison is low on supplies. May trade or run outta arrows
28-Freaks! The garrison is all mutated in an identical way. What's the score here?
29-Lotta time on their hands. They make cheese or wine or tapestries here.
30-Lotta time on their hands. They gamble on basilisk fights or whatever here.

If the same complication is rolled twice, use one of these (d6)
1-Captain of garrison is cordial and curious about outsiders. Or pretending to be…
2-Captain is insane
3-A member of the garrison falls in love with a party member
4-A member of the garrison owes a party member a favor
5-Captain intends to capture PCs and pump them for information about some intriguing scheme they actually know nothing about
6-Interior architecture is irrational--dead ends, pointlessly sloping passages, etc.

(Automated version here.)