A prevalent part of my campaign world is airships and the sky in general. Terra firma is know to be a desolate place rife with untold horror.
CoS soldiers are feared because they can infiltrate any structure with an entry or landing zone exposed to the sky. CoS extractions have a high success rate for their ability to get in and out before the enemy is even aware of their presence. Dropping from an airship, they can be on top of a target within seconds and using boots of jumping they can glide away at high speeds as en effective escape method.
Conducting a drop assumes that a character has a Convenant of Silver drop cloak, which is effectively a primitive but magically imbued wing suit. The cloak is tied at the shoulders and has stirrups of leather stitched in the cloaks corners.
The cloak must be attuned and CoS soldiers are known to guard their cloaks with adoration, some even naming them and treating them as a loved one.
When the feet meet the stirrups, the cloak stiffens slightly, creating a wing behind the individual. Different cloaks can form into different patterns, all of which are designed to be functional. Once attuned, the cloak can be mentally controlled and guided.
Gameplay
Keep it simple.
Whenever a character fails, they have to recover. This means making the same check at a disadvantage each turn until they succeed. How many rounds do they have? I'll answer that with another question: How far away is the ground?
Keep this in mind: Wingsuiters die in real life, but not as many you might think.
Flowchart of a Drop
Initial Drop
Athletics or Acrobatics DC 10
Akin to a diver dropping backwards off a boat. Success means everything goes good. Failure means you're starting off recovering.
Recovering
Athletics or Acrobatics DC 10
When you screw up during the drop, it means you're tangled in your cloak, you missed a stirrup or both the stirrups, one of the stirrups came off for some reason, you got a cramp in your leg, or one of your shoulder snaps came undone.
Recovery means getting untangled, getting your feet in place, fixing your shoulder harness, etc; failure means you continue tangled and fail every obstacle on the way down. If this means crashing, you crash. Critical failure means you get disadvantage on your next recovery test as things have now gone from bad to worse.
Challenges
Perception or Insight DC 15
Sighting obstacles properly while falling affords the character advantage. Failure doesn't incur any penalty; critical failure, is up the DM. Natural 20 is a pass on the next test, or perhaps advantage on all tests in the drop. This is active, not passive.
Athletics or Acrobatics DC 10-15
Obstacles between the characters and their target are what make the drop fun for the whole family.
Try to imagine heroic soldiers dressed in heavy armours made of woven umberhulk fibers hurtling among floating islands with trees, passing airships and skiffs as they soar towards a target.
Each obstacle should make sense, don't ever repeat an obstacle, not even as a sandwich element.
Yes, this means your entire asteroid field could be one test, but let's break that down.
The asteroid field is made of a lot of different types of asteroids; let's pick the best ideas we have and wax over the rest.
Asteroid field: Characters rolls athletics or acrobatics as they begin the drop, they can perceive if they so choose, the dodge most of the asteroids with another athletics or acrobatics roll, there's a giant worm that sprouts out of one of the asteroids and it attacks two of the passing characters (roll at random), come upon landing area and roll athletics or acrobatics for landing.
It should be noted that landing zones may vary in difficulty given what the target may be.
Otherwise,that's literally it.