Dangling on the end of a rope 20 stories in the air isn’t the most prudent thing to do, usually, but it looks so damn cool that it’s a major part of superhero comics. The in-game benefit of swinging is that you can cover a bigger distance than a jump, without nearly as much chance of falling to your pulpy death.
Swinging as Movement
Swinging on a rope is part of a move action, like jumping or climbing, but you swing twice as fast as your size and encumbrance would normally allow (NB: Super Speed does not increase swinging speed). If you swing for a distance of 30 feet, it counts as only 15 feet of your movement.
To swing, you need a rope or other tether, like a strand of Webbing, that is connected more or less equidistant between your self and the spot you want to land on. You also need some room below you because the arc the swing will take you down before it goes up again. If it’s pertinent (e.g., you might actually hit the ground), then you need an extra 5 feet downwards for every 25 of total swinging distance. A 50-foot swing requires about 10 feet of extra space below you, for example. If there isn’t enough space, then you must make a Reflex save, DC 15, or you hit the ground and take falling damage as normal. If you make the save, then you hit the ground running. You can substitute a Tumble check for the Reflex save, at your discretion.
To determine success or failure for the swing, make a Tumble check DC 14 (base DC 10, +4 equipment bonus for the rope). The DC rises by +2 for every 5 feet out of true the swing is. “Out of true” means one of three things: (1) the start point and end point are at different heights, (2) you have to swing in a lateral arc (i.e., around instead of straight), or (3) the fixed point of the tether isn’t equidistant between your start and end points. You also add +2 for every 50 pounds over a light load.
Example: If the rope’s fixed point were 5 feet closer to you than your target point or 5 feet to the left (so that you have to swing in an arc), the DC would be 16. If the end point of the swing were 10 feet higher than your starting point, the DC would be 18. If all three factors were out by 5 feet, then the DC would be 20. If all three were out by 10 feet, the DC would be 26. And so on.
This can get to be a complicated set of calculations, so GMs are encouraged to eye-ball the DC. GMs are also encouraged to let “flavour” swinging go without tedious checks. If it’s just for show, to make the character look cool, then don’t sweat it. If it’s actually a risky manoeuvre, then enforce the rolls.
If you succeed, you land on your target square, on your feet. If you fail the check, you land prone and take 1d6 NL. This does not provoke an attack of opportunity, but standing up does. If you fail the check by more than 10, then you fall in mid-swing at a point to be determined randomly.
For example: You’re attempting to make a 50-foot swing with a fixed point 15 feet off of a straight line, 5 feet too close to you, and landing on a rooftop that is 10 higher than where you’re standing. At +2 to the DC for every 5 feet out, that’s a DC 24. Difficult, but not impossible. If you were to roll a 25, you would land clean. If you were to roll a 20, you would hit the ground like a sack of wheat, but you would just get the wind knocked out of you. If you were to roll a 10, you would fall right off the rope, into the traffic and soon-to-be traumatised bystanders, below. We hope you have clean underwear on.
While you are swinging, you lose your Dexterity and dodge bonuses to Defence, but you are a rapidly-moving target, the same as if you were running, and therefore also get a +2 to your Defence. If you are hit for damage while in mid-swing (between rounds or by a Readied action), you must make a Fortitude save with a DC equal to the damage you took. If you fail, the pain and stress of the taking damage causes you to involuntarily let go of the rope. For Swinging Attacks, see the previous section.
Jumping at the End of a Swing
If you let go of the rope when it’s more or less horizontal (at the end of your swing), you can make a Jump check as if you had a running start. You swing your body upward to achieve height, or throw it forward to achieve distance. Thus, you can swing across a chasm, let go of the rope at the other end, and make a fresh Jump check, all as part of the same move action.
Kicking Off in Mid-Swing
Although you cannot change your swinging trajectory in mid-swing, you canpush off of a solid, anchored point, for example swinging against the side of a building and kicking off of it. If you swing at an angle to the wall, you can make a Jump check as if you had a running start. The result of the check indicates how far along the arc of the swing you manage to get (i.e., how far you launch yourself away from the wall). If you swing straight into a wall, you can repel off of it as if you were making a Jump check without a running start. The distance, again, indicates how far you manage to get from the wall, along the arc of the rope’s length. Swinging directly into a wall, however, causes the same amount of damage as falling, but you can reduce that damage just as you would a normal fall (i.e., through a Tumble check, or Catfalling).
If you have Webbing, you can fire a fresh strand as a standard action each round. Thus, you can change direction by affixing a fresh strand to a new anchor point and letting go of the old strand. This whole chain requires a move action (swing) and a standard action (fire strand). If you’re doing it as a form of movement, out of combat, you just need to make a single Tumble check, as part of your move action, with a base DC of 20. Failing means that you simply didn’t manage to affix a second strand and you’re still on your original strand. Failing by 10 or more means that you fall. At the end of this full-round action, you’re again in mid-swing and ready to start the whole thing over again the next round. You pick a new direction in which to swing at the beginning of this full-round action.
GMs are, of course, free to increase the DC for performing swings in difficult environments, like through a very skinny alley, between moving vehicles, or the like. In fact, it’s worth noting that the GM always retains the right to increase DC’s as she sees fit.
If you’re out of combat and swinging as a form of transportation, then you can make these Swinging checks once per minute instead of once per round. If your Tumble bonus is high enough that you’re guaranteed success, then rolling isn’t necessary because natural 1’s are not automatic failures on skill checks. Lucky you!
You can, in theory, keep swinging and switching ropes indefinitely. However, it is extremely tiring. Moving in this way is like running. Thus, you can keep swinging for a number of rounds equal to your Constitution score, but once those rounds are expended you must make a DC 10 Constitution check. The DC of this check increases by 1 every round until you fail or finally arrive wherever it is you’re going in such a damn hurry.
If you fail this check, you just don’t have the energy for another swing and you must rest for 1 minute (10 rounds) to get your breath back. You can rest while hanging off of your rope, but every time the strand swings with you on it as dead weight, it looses 1 foot of distance and height at both ends, so after 10 rounds, you’ve lost a total of 20 feet (10 feet at each end). You can also climb down off of your rope, if that’s an option, and rest on the ground for a mere 60 seconds. While resting, you are not at any penalties. You just don’t have the energy to do any more swinging manoeuvres or to employ the Run action.
Falling While Swinging
If and when you fall off a rope, you fall at a slight angle in the direction in which you were swinging. For every 20 feet you fall downwards, you also drift 5 feet in the direction of your swing. If this causes you to impact a solid surface, like a building, then you take damage as if you’d fallen to that height, and then you start to fall straight down (i.e., you land in that same square). For example, you were to fall at 120 feet in the air and drift into a building after 40 feet, you’d then take damage as if you’d fallen 40 feet. If and when you hit the ground at the end of that fall, you’d take damage from the whole fall: 120 feet.
However, there is no need to calculate the exact number of feet you travel laterally unless the game calls for it. If, for example, you might drift next to a building that you could grab on to to keep from falling, then calculate your lateral movement, but if you’re just spiralling through empty air, there’s no need to burn the brain-cells doing the math.