The Weighted Companion Cube is similar to the Weighted Storage Cube, but so much more cute. When holding it in your hand it will help you regenerate half a heart once every 5 seconds. The Weighted Companion Cube is a free moving block, meaning it can be pushed around anywhere in the world.
To create this beautifuly majestic cube that emits hearts when you click on it, place your Weighted Storage Cube on the ground, and then simply right click on it with a poppy. Then you can break your newly created companion and carry it with you.
Video Tutorial Edit