For upcoming Gehenna hex-crawl piece, I am snapping off this mercenary band generator.
In particular I had in mind the volcanic slopes of Khalas, known as 'the Gentle Land', where the front lines of the Blood War surge back and forth but the broken landscape means there is no static, fortified line and lots of room for wandering around without being seen - or without seeing and thus avoiding some other band of ne'er-do-wells abroad beneath the Furnaces. I like about Gehenna is the cragginess of the place - the terrain is so difficult to deal with that again, it makes sense that even though the Blood War rolls over this place, you can move around unseen and avoid the clashes of mighty armies.
Khalas was where I set one of my longer running campaigns and I think it is a great part of the lower planes for many reasons. Least horrible of the lower planes you could pitch into Gehenna and while it is dangerous, it is plausible that you could survive there long enough to think you way out. Pitch up on Avernus or into the Gray Wastes and the clock is ticking for you. All of the 'off-cardinal' lower planes are generally more survivable because they do not have a native power of the lower planes - no devils, no demons, in theory the yugoloths live here but they hold the place with a lighter grasp if so. The noted local powers of Gehenna are the Barghests - described as the 'only true natives' of Gehenna. Taking this as true, then Gehenna is sufficiently easy to slip about in that CR4 blue goblin lycanthropes can hold dominion where the rulers in the planes on either side are CR13 Ultroloths and CR20 Pit fiends.
Altogether, I read that as a canon license for cunning lower level adventurers to slither about in the shadows without that being against the spirit of the place. Below you will find some tables for setting the scene for the local Blood War and the mercenary bands players could run into.
How goes the Blood War just now? (2d6)
2 Local rebellion - locals are pushing back against Blood War incursions and hired enough mercenaries to cause disruption to the front lines. There is a new player (barghest, renegade yugoloth, followers of a local god)
3-4 "This time is different" - An attempted breakthrough at a surprising location is turning into a terrain-driven defeat for the aggressors, proving are again why the common battlefields are chosen again and again over the aeons.
5-9 "Same old story" - another push for the Bridge at Khalas, a battle on the Styx or a thrust along the Great Road is drawing in more and more of the local forces. The outcome is anyones bet just now, mercenaries are charging sky-high rates.
10-11 "Who could have seen" - A feint has won a foothold; the aggressor has broken through enemy lines and is rolling back the foe across a broad swathe of the plane. Both sides are rushing reserves to the new front lines, combat is happening well away from the usual fortifications, the scales of the Blood War tilts.
12 "The Long way around" - flare up somewhere back from the front lines after infiltration by another planar route - portals from Sigil, the Infinite Staircase - situation is fluid, with a small, powerful force of aggressors loose behind enemy lines. Reserves are on the move to contain or link-up.
What shape are this bunch in? (d12)
1. paid and feeling rich - rolling off an easy money contract and looking for good times
2. rested and resupplied - on their way to really ruin someones day
3. bloodied but victorious - the plan went well, victory was crushing, trophies are proudly displayed
4. on maneuvers - on campaign, pickets are out, hunting for the foe
5. forced marching - weary and bedraggled, hustling to get to where they are needed
6. returning to barracks - battered and understrength, chewed up by the unforgiving Blood War
7. dug in - in a temporary camp, holding these particular slopes of Gehenna
8. fortified - occupying a structure, hungry and low on supplies
9. regrouping - the last fight went badly, they are seeking new ground to take a stand
10. retreating - soldiers stream past, wounded and missing gear, seeking their leaders
11. broken - scattered elements retracing a trail of discarded equipment and shattered baggage
12. starved - the last remnants of the band, burying their fallen commander
What is the core of this warband? (2d6)
3. Celestial Raiders
5. Abandoned siege-beast crew
9. Planar mercenaries
10. Lawful brigade
11. Local militia
More anon on who/what is making up this warband.