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Minecraft version: 1.12.2 [change as necessary]
Wizardry version: 4.2.10 [change as necessary]
Environment: Singleplayer/LAN game/Server [delete as necessary]

Issue details: Any time the Grapple spell is used (on the player by hostile mobs at least, i don't have the spell book yet) there is a client crash. Curiously, servers don't crash.

Other mods involved: [only list mods that are relevant to the problem]

Link to crash report (if applicable): https://pastebin.com/M6BhjQdn

Ah yes, I can see what's happened there, that's my fault for not null checking. Thanks for reporting.