Block Break Warden

Block Break Warden is a client-side Fabric mod that restricts which blocks a player is allowed to break. Its three modes are Off, Whitelist and Blacklist, cycled through a GUI with a hotkey. When a player tries to break a forbidden block, a warning appears on a line above the hotbar, with an optional sound. Holding down the left mouse button to spam attacks triggers the same warning.

The whitelist and the blacklist are independent lists, and each is edited separately in the GUI, with a switch for choosing which one is being edited. Each list can hold two kinds of entries: a single block ID or a block tag. Aiming at a block and pressing N puts it into the list belonging to the active mode; pressing N a second time on a block already in that list takes it out again. The Off mode does nothing, so a player should pick a mode first.

The restriction works through AttackBlockCallback and applies on the client only, so it limits what the player breaks and does not protect blocks from other players on a server. The GUI opens through Mod Menu or directly, and the hotkeys can be rebound under Options, Controls, Key Binds, in the BlockBreakWarden category. The mod is published for Fabric only, for 19 release versions across 1.20 – 1.21.11, and the code is all rights reserved.