Paint over a 300ft cube of the current plane to match your image. Whatever objects or creatures you paint become real and behave as you wish, things that you paint don't have to follow traditional physics.
You cannot override or erase creatures that existed prior to your edits. You may only have one of these "Living Canvas's" active at a time.
Creatures created can only exist within this 300ft cube and don't count against your max summons. They turn into regular paint upon attempting to leave the cube.
Your brush sweeps across empty air, and the world bends. Mountains tilt, oceans ripple upward, and beasts crawl from dripping pigments. Inside the cube, trees float sideways and castles rest upside-down—real, until they wander too far.