Minecraft anticheat guide
FairPlay Scaffold Movement Momentum Checks Explained
How FairPlay's movement momentum checks for scaffolding compare speed, slowdown and placement timing, and what staff should verify before acting.
What do the movement momentum checks watch?
Movement momentum checks watch how a player's speed, direction and slowdown change around placements. Six FairPlay checks sit here: ScaffoldAcceleration, ScaffoldNoDecel, ScaffoldJumping, ScaffoldSprinting, ScaffoldStraightWalk and ScaffoldAverage. They compare how the player moves with the timing and spacing of the blocks placed.
Which movement patterns do they target?
These checks target bridging that moves in a way normal movement does not explain. Some look at speed changes, some at whether the player slows down after a placement, and others at how steady the timing between placements stays.
What legitimate movement can resemble these checks?
Movement changes a lot during normal building. Players sprint across gaps, stop to line up a block, jump onto a new line and slide across slick ground. Each of these changes speed and spacing, and each can match a check's pattern.
How should staff read momentum alerts?
Momentum alerts are weak on their own because many normal moves look alike. Read them with the surface, the active effects and the bridge shape in view. A long straight bridge with even timing, on the same route, across several sessions, is a better reason to review than one short run.
What should you tune only in staging?
Momentum checks depend on how speed and timing are sampled, and on how many placements they need before a run counts. Change those settings only on staging. Test sprint-jumps, straight bridges, ice and slime routes, and a potion-effect session. Compare alert output before and after each change.
How do surfaces and effects change momentum?
Surfaces and effects change how speed builds and fades, so the same route can produce different momentum on different ground. Ice lets the player keep sliding after a stop. Slime slows and bounces the player. Soul sand and water change movement speed. Speed and slowness effects shift acceleration for their whole duration. A sprint-jump across a gap brings a sudden speed change that the check can read as an unusual step.
Build a small route set for staging before you judge any momentum alert. Include a straight flat bridge, a sprint-jump line, an ice line and a potion-effect run. Run each route the same way every time, and record alert output before and after any setting change.
How should staff review a sprint-jump?
A sprint-jump is a short, fast move, so review it as a sequence. Look at the gap length, the speed before the jump and the landing surface. Then check whether the next placements slowed the way an ordinary bridge would. A sprint-jump followed by steady, ordinary placements is different from a run of identical jumps across many gaps.
Movement effects such as speed and slowness change the whole run, so note them even when they are short. An effect that ended mid-route can make the second half of a bridge look different from the first.
Keep the sprint-jump route out of the main test set until the flat bridge and ice line are stable. Once they are, add the jump line. Write down the route length, the number of gaps and each landing point so you can rerun the exact same route later, and so a changed result can be traced to one route.
What have we not verified?
This article reports no detection rate, error rate or staging results. Each description reflects what the check compares, based on its name. Test the behavior on your own server and surfaces before relying on it for enforcement.
FAQ
Why does a sprint-jump trigger a momentum alert?
A sprint-jump changes speed quickly, which can resemble a check's pattern. Review it with the gap, the surface and the player's route before deciding.
Does a missing slowdown alert mean the player is speed hacking?
Not by itself. Ice, slime and movement effects can change how a player slows down. Confirm with a recording and the surface under the player.
What does an average timing alert tell us?
It means placements came at an unusually even pace over a recent set. A steady player can produce that, so compare it with the player's normal rhythm.