This is a ? block from the Mario universe!
I printed mine with a raft, no supports, .2mm layer height, 215C PLA, and 15% infill.
I used a 15% infill because the difference in plastic used and print time were minimal, but a 10% infill would likely be more than enough. The undersides of the question marks drooped a little without supports, but not enough to really notice. I also printed this with a raft, but I don't think it would make a difference.
When designing this block I tried to match the original Mario question block design as close as possible. In Solidworks, I started with a perfect cube, created one side with a protruding question mark and four circles, beveled all of the edges, and then copied it to the remaining three sides. The print may appear to be uneven because the x and y are equal while the z measurement is shorter, but this is simply because the top and bottom of the cube are flat (do not contain protruding question marks) while the other four sides are not.