This is the D&D Logo. I found myself wanting to use it in my own designs so I thought I might not be alone. So I've created it in Fusion 360 and have included that file with the STL so that you can use it too, if you like.

The D&D Ampersand (&), alone, can be found here: https://www.thingiverse.com/thing:3325895

The full D&D Logo with DUNGEONS & DRAGONS spelled out completely can be found here: https://www.thingiverse.com/thing:3326260