PvB

A Minecraft 1.21.1 Fabric mod that gives you a PvP opponent worth practising against.

The problem it solves is that you can't get better at Minecraft PvP alone. Command-block dummies don't fight back, mobs don't play like people, and finding a human who'll duel you fifty times in a row to drill one matchup is hard.

The bot is a real player. Not a mob wearing armour — an actual ServerPlayerEntity driven by an AI. That distinction matters more than it sounds: it means the bot inherits the genuine 1.9 attack cooldown, real sprint-reset knockback, shields with the correct 5-tick raise delay, authentic crystal placement rules and explosion falloff, totem pops, mace fall-damage scaling. Nothing is approximated. If you beat it, you beat the actual mechanics.

It's built to feel human, not perfect. Every reaction is a sampled delay, never a constant. The crosshair carries a slow drifting bias plus per-tick jitter, so it wanders like a hand on a mouse instead of snapping. There's a "focus" value that drifts across a fight, producing the they had a bad ten seconds effect. Mistakes cluster rather than firing independently — one error opens a short window where more are likely, which is what tilting actually looks like. Item switches cost real time and can grab the wrong hotbar slot under pressure. Each bot also rolls permanent quirks at spawn, so two Master bots don't play identically.

Difficulty changes skill, never the toolset. An Easy bot owns crystals, a mace and pearls exactly like a Master bot — it's simply bad at using them. It aims 26° off, reacts in a full second, forgets its totem, and pops crystals so slowly you walk out of the blast. Master reacts in ~1 tick and tracks you at 68°/second. Nine attributes drive all of it, and they're editable in a config file.

Rounds are built for repetition. Build an arena, pick a difficulty and kit, hit Fight. Whoever would die doesn't — the lethal hit is cancelled, so nothing drops, there's no death screen, the arena rebuilds itself, and a rematch screen appears a second later. You can run twenty rounds back-to-back without ever picking up loot or walking anywhere.

There are eleven kits — Crystal PvP, sword-only, potion, mace, UHC, Sumo and more — and they're independent of difficulty, so "Master skill, sword-only kit" is a thing you can pick. Restriction is real: a bot with no crystals genuinely never uses them, because the AI reads the inventory rather than a difficulty label.

It's server-side, so a whole server of vanilla clients can fight it with nothing installed.