Catzilla is an OpenGL 4.0 and DirectX 9/11 benchmark for Windows that incorporates a parallel graphics engine that can take advantage of multi-core CPUs.
The benchmarks consist of a literal giant cat fight scene, which stresses both the CPU and GPU, and a set of smaller benchmarks to test CPU rigid body physics, GPU smoke simulation, fur rendering, and liquid simulations.
More information can be found here.
A total score of 1608 for the CPU and GPU test in Catzilla confirms that the XPS 18 is not a gaming powerhouse. However, it did successfully complete the entire benchmark.