Auto Lunge swap

Auto Lunge Swap

One key. Tick-perfect lunge swaps. No hotbar gymnastics.

Auto Lunge Swap is a client-side Fabric mod for Minecraft 1.21.11 that performs the spear lunge swap for you: it selects your Lunge spear, jabs, and selects your previous item again — all inside a single game tick. Hold the key and it repeats every time the attack bar is ready, which with a bare fist means a lunge every 5 ticks (4 per second) instead of the spear's native 13–23 ticks.

Features

• Press once, lunge once — a tap is remembered for a few ticks, so slightly early presses still fire.
• Hold to chain — lunges keep coming as fast as the carrier item allows.
• Automatic carrier — you can hold anything when you press the key. The mod parks you on an empty hotbar slot (fastest possible recharge), lunges from there, and puts your original item back in your hand when you release the key.
• Automatic spear detection — uses the hotbar spear with the highest Lunge level; optionally pin a fixed slot.
• Safety checks — respects vanilla's hunger requirement (Lunge needs food level > 6), never interrupts eating/drinking/charging in the main hand, and never fires with a screen open.
• Toggle key with an action-bar message, so you can switch it off mid-session.
• Zero HUD clutter — nothing is drawn on screen. Optional debug log line per lunge.
• Fully vanilla input path — the jab goes through the same client routine as a real left click.

Controls (Options → Controls → Auto Lunge Swap)

Why the carrier item matters

A spear jab is only accepted when the attack bar is 100 % charged, and the bar recharges with the attack_speed attribute. The server refreshes attributes from your equipment just once per tick, so a jab performed in the same tick as the item switch is judged with the attack speed of the item you were holding before — while the held stack (and its Lunge enchantment) is already the spear. Whatever you hold between lunges therefore sets the pace:

Configuration — config/autolungeswap.json

Requirements

• Minecraft 1.21.11 (the spear and Lunge were added in this version; 26.x builds are not supported)
• Fabric Loader 0.16+ and Fabric API
• Java 21

Please read before using

Attribute swapping is a vanilla bug (MC-28289). Mojang has stated it is not supported functionality and intends to fix it — it was removed in 26.2 pre-release 2 and only temporarily restored in pre-release 3. Many PvP servers and anti-cheats treat swap macros as cheating. Use this mod in singleplayer or on servers whose rules explicitly allow it; you are responsible for where you run it.

Spamming lunges is hungry work: every lunge costs 4 × Lunge level exhaustion, so a Lunge III spear burns roughly one drumstick and a half per lunge. Keep food handy.