Ermac's Spectral variation might have a glitch or something. Here's why:
If you levate, and you must be using said variaition, and then do a force blast or teleport, you get a free meter. I played through the MK1 tower using this and got 23 X-Rays totals. 23! Just a quick note in case you either want to avoid players who use this or if you want to boost your W/L ratio.