4.0.0-rc.2

Beta release candidate for Minecraft 26.1, with separate Fabric and NeoForge builds. This update expands configurable encumbrance effects and is intended for gameplay and balance feedback.

Added

• Configurable weight-based hunger exhaustion for walking, sprinting, water swimming, and jumping. Defaults add up to 50% to existing activity costs and up to 0.01 exhaustion per block of ordinary walking. Costs follow the selected walking slowdown mode, with no added idle drain.
• Optional upward swimming restriction, disabled by default. It blocks player-driven ascent and edge-exit boosts at full capacity in the selected fluids, preserves external currents and bubble impulses, and provides throttled action-bar feedback.
• Configurable knockback resistance based on physical carried weight: defaults add up to +0.4 resistance at 1,000 pounds, independently of carrying-capacity bonuses. Stacks with equipment without adding a status effect; explosion resistance is unchanged.
• Server settings and operator controls for each new effect, including independent toggles and configurable thresholds or caps.

Changed

• Fall penalties now increase gradually: no added damage through 90% capacity, about 1.29 times normal damage at 100%, and a maximum of 2 times at 125%.
• Swimming and sinking have independent gradual curves. Defaults apply to water and lava, starting above 90% capacity and reaching 50% horizontal swim input and 2 times fluid gravity at 100%.
• Player weight and settings updates are sent when state changes, instead of resending unchanged values every second. Join, respawn, dimension travel, and reconnect still receive current state.

Fixed

• Encumbrance-blocked ground jumps no longer consume exhaustion or increment the server jump statistic.
• Weight no longer turns harmless short or cushioned falls into damaging falls. Normal fall protection and landing-block behavior are preserved.

Compatibility and upgrade notes

• Requires Minecraft 26.1 and Java 25. Install the matching loader jar on both client and server.
• Verified baseline: Fabric Loader 0.18.5 with Fabric API 0.144.0+26.1, or NeoForge 26.1.0.1-beta. Cloth Config 26.1.154 is required on Fabric and on NeoForge clients; NeoForge dedicated servers can omit it.
• Update clients and servers together: the configuration network protocol changed from RC1.
• Existing server configuration files use the new defaults for missing effect settings without being rewritten during loading. Exhaustion and knockback resistance are enabled by default; upward swimming denial is off. Operators can adjust these through server settings or edit config/heavyinventories-server.json and run /heavyinventories reload.
• Disabling the new effects leaves the existing walking slowdown and ground-jump restriction in place. Strength and carrying enchantments reduce capacity-based strain; Surefooted's walking benefit does not remove exhaustion, fall, or fluid penalties.
• The default carrying capacity remains 1,000 pounds. Item weights and datapack overrides are unchanged in this update.
• Both loaders passed dedicated, integrated, and separate multiplayer checks. Longer survival balance testing, high-latency behavior, and third-party movement/combat/backpack integrations remain unverified.

Please report balance feedback, especially for sustained travel and recovering from overload in water. This is a beta candidate, not a final stable release.