Minecraft anticheat guide
NoFall and Ground Spoof Cheats in Minecraft Explained
How NoFall and ground-spoof cheats fake the on-ground flag to avoid fall damage, what that mismatch looks like, and how to test fall checks safely.
What do NoFall cheats send to the server?
NoFall cheats send movement packets that claim the player is on the ground while they are falling. The server applies fall damage based on the fall distance it tracks, and that tracking depends on the on-ground value in each packet. A false on-ground flag can stop the damage from being applied. Anticheats compare the reported ground state and vertical movement with the blocks the player could actually stand on.
Why does the ground flag matter so much?
Each movement packet carries an on-ground value. The server uses it, together with the position history, to decide when fall distance builds up and when a landing happens. A client that reports on-ground while its position drops across several ticks contradicts the physics the server expects.
Honest players can look similar for one tick. Stepping off a ledge, a block placed under the player, slime blocks, water, and some teleports all change the ground state quickly. A check that reads one tick alone will misfire, so look at the sequence of several ticks.
Which ground patterns are suspicious?
The table compares normal landings with the patterns staff usually report. Use it as a review guide, not as proof on its own.
| Situation | Expected ground state | Suspicious pattern |
|---|---|---|
| Walking off a one-block ledge | Airborne for a short drop, then grounded | Ground flag stays true while Y falls |
| Standing on a solid block | Grounded with no vertical change | Ground flag false while still on a solid block |
| Landing from a long fall | Grounded on the landing tick | Fall distance resets with no damage applied |
| Falling into water or onto a ladder | Not treated as a normal landing | Damage cancelled on repeated falls onto solid ground |
How do you test fall checks in staging?
Build a controlled test area so every fall has a known height and landing block. Keep the same server software and anticheat build as production. Record the damage taken, the fall distance, and every alert for each drop. Then repeat the drops with the conditions that create honest false positives.
# Replace the check name with the fall-related check your anticheat reports.
grep -i "<fall-check-name>" logs/latest.log | tail -n 50What limits does a fall check have?
Expected fall damage changes with enchantments such as Feather Falling, with potion effects, and with server plugins that alter damage or teleport players. Those factors change what an honest landing looks like, so test them together with the anticheat. Start with alerts only. Decide on mitigation after your staging results show that the rule is safe for your server.
Which fall settings should you review first?
Review your damage rules, plugin hooks, and any teleport plugins before you read fall alerts. A single plugin that resets fall distance can create alerts that look like spoofing. Write down each plugin that touches damage so the review can account for it.
What have we not verified?
We have not tested any anticheat against NoFall or ground-spoof clients, and this article makes no claim about detection rates. Results depend on server version, latency, world layout, and the plugins you run. Repeat the staging steps on your own build. Keep a short written record of each fall, including the drop height, the landing block, and whether any alert appeared, so a suspicious case can be compared with known honest falls.
FAQ
Does a NoFall alert prove the player used a cheat?
No single alert proves that. Check the alert sequence, the blocks around the player, and whether the fall passed through water, a slime block, or a ladder. Repeated alerts across different falls carry more weight than one line.
Should a fall check cancel damage or only alert?
Start with alerts only. Use your staging results to decide whether any mitigation is safe for your server, and read your anticheat's documentation for the options it provides.
Do plugins that change fall damage break fall checks?
They can. A plugin that alters damage or moves players may create landing patterns the check does not model. Test those plugins together in staging before you trust the alerts.
How long should a fall test run?
Run enough drops to cover each landing type several times. A few falls can pass by chance, and a short test cannot show whether an alert repeats during normal play.
Can a plugin that resets fall distance cause fall alerts?
It can. Some plugins reset or modify fall tracking when a player teleports, respawns, or changes worlds. Those events can look like a landing without damage. Check your plugin list against the alert times before you review the player.