Free Runners are a pair of Mekanism boots that’ll take away all of your fall damage for as long as they’ve got energy in them. To use them you only have to wear them, and each point of damage that they absorb costs 20 FE (50 J), so a full charge of 25,600 FE is enough to cover a huge number of falls before they need topping up.
In their default mode they also let you walk straight up a full block without jumping, and they stop blocks like 
Soul Sand from slowing you down. They can be upgraded into 
Armored Free Runners later on, which do all of the same things and give the armor of 
Diamond Boots as well.
How to Get It
Free Runners are crafted from 2 of each of the 
Basic Control Circuit, 
Infused Alloy and 
Energy Tablet. All three are things you’ll be making anyway for your first machines, so these are usually the first piece of Mekanism gear that players are able to put together.
For the Armored Free Runners you’ll place a pair of Free Runners in a 
Crafting Table with a 
Block of Steel, 2 
Diamond Dust and 2 
Bronze Ingots. They have 3 armor and 2 toughness, which is the same as Diamond Boots, whereas the plain pair has no armor value at all.
How to Use It
Fall Damage
With Free Runners on your feet, any fall that would have hurt you is paid for with energy instead, at 20 FE for every point of damage, where a point is half a heart. A fall that’d normally deal 10 hearts of damage will cost 400 FE, and a full pair is able to soak up 1,280 points in total.
If there isn’t enough energy left to cover a whole fall, they’ll absorb as much as they can pay for and you’ll take the rest. Once they’re at zero they do nothing for falls, so it’s worth checking the charge in the tooltip before you jump off anything tall.
Step Assist and Movement
In Regular mode you’re able to walk up a full block as if it was a slab, which makes running across rough ground a lot smoother. It’s switched off while you’re sneaking, so you can still edge up to a drop safely, and the code doesn’t check for energy here, which should mean it works on an empty pair as well.
Regular mode also stops you being slowed by blocks like Soul Sand and the 
Honey Block, as the boots add a level of movement efficiency while they’re worn. Neither of these extras uses up any charge, they’re only tied to the mode that the boots are in.
Modes
There are three modes, and you’ll change between them by pressing the Feet Mode Switch key while wearing the boots, which is B by default. A chat message tells you the new mode each time, and it’s also shown on the item’s tooltip as the Runners Mode.
| Mode | Fall Protection | Step Assist | No Slowdown |
|---|---|---|---|
| Regular | Yes | Yes | Yes |
| Safety | Yes | No | No |
| Disabled | No | No | No |
Safety is there for when the step assist gets in the way, like when you’re building and don’t want to walk up onto every block that’s in front of you. You’ll keep the fall protection in that mode, whereas Disabled turns off everything, so the boots stop using energy.
Charging
Free Runners run on energy, so they’re charged like any other powered item in the mod. The simplest way is to drop them into the charge slot of an Energy Cube, or you can stand on a 
Chargepad while you’re wearing them, which will charge them on your feet.
They take in up to 128 FE a tick, so an empty pair will be full again in about 10 seconds. With the MekaSuit Boots on instead, those handle falls themselves and Free Runners aren’t needed anymore. Before then, the next piece of gear to look at is the Scuba Mask and Scuba Tank, for working underwater.
FAQ
You only need to charge them and wear them in the boots slot, as they work on their own from then on. Fall damage is absorbed for 20 FE a point, and in Regular mode you’ll walk up full blocks as well, with the Feet Mode Switch key (B) used to change modes.
They’re charged with energy, either in the charge slot of an Energy Cube or by standing on a powered Chargepad while they’re on your feet. They hold 25,600 FE and take in 128 FE a tick, so it only takes around 10 seconds to fill an empty pair.
They’ll absorb 100% of a fall as long as there’s enough energy to pay for it, at 20 FE for each point of damage. If the charge runs short part of the way through, only the share they could afford is taken off, and an empty pair gives no protection either.
Safety mode keeps the fall protection but turns off the step assist, so you won’t climb onto full blocks by walking into them. It’s useful when you’re building or working near edges, and you can switch back to Regular with the same key whenever you want it.
