Eh... people should really get past that assumption that 2D isn't as intensive as 3D. Generally ya, 2D games will probably run better than 3D, but the problem is people assume because a game is 2D it will always be able to outperform a 3D game. "I CAN RUN <such and such 3D game> ON MY PC BUT YOUR CRAPPY 2D GAME STILL MANAGES TO SLOW DOWN!!!" It all depends on what the game is doing. At the lowest level many 2D games are rendering their textures to polygons anyways(even Graal does this, if you zoom in on your iDevice you can see where the textures don't quite line up right at the edges of the quads due to the bilinear filtering). Then factor in other things that might be more intensive than graphics(intensive cpu factors, such as in Terraria: lighting. Shaders and such are another culprit) it's not unlikely that a 2D game can run worse than a 3D one.