Criticals

A critical hit deals 1.5× damage, but the game demands a real fall for it: the player must be off the ground and moving down, not in water or on a ladder, and on 1.9+ also not sprinting and with the attack meter nearly full. Criticals fools that check — it sends the server a tiny fake hop or spoofs the on-ground flag — and every hit becomes a crit.

An honest player has to jump and time the fall to land a crit. The cheater lands crit after crit standing on flat ground; in sword and axe duels, in BedWars and on anarchy that's bonus damage on every hit with no loss of tempo.

• Crit particles on nearly every hit while the cheater stands or walks on flat ground
• Barely visible hops before each hit, lower than a normal jump
• Crit after crit in a fast combo where an honest player couldn't have jumped and started falling

The server checks the heights the client reports against physics: without Jump Boost a jump starts at 0.42 blocks per tick and then follows gravity. A hop of a few hundredths of a block on flat ground doesn't fit that curve, and neither does an ‘in the air’ flag from a player standing on a block. So a jumpless crit gives itself away to both physics and packet analysis.

Honest exceptions exist: slabs, stairs, snow layers, carpets, block edges and bubble columns produce unusual heights. One odd height is a reason to look closer; evidence is a steady stream of crits with no fall before them.