Pen of Shapes (5e Equipment)
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When you write or draw with this pen, you can use a reaction or bonus action to bring something you've drawn to life, which jumps off the object you made it on and appears as a 3D animated ink construct with the same statistics as a cat, though it cannot attack. It is friendly to you, and follows your commands. It does nothing if you give it no commands, except following its curiosity with reckless abandon. Each ink construct seems to have the same memories as the last, allowing you to teach them things, though their nature prevents them from learning anything substantial like attacks or spells.