I should really make these things into a series or something. "-ing with Pokemon", in which some verb goes in front of the "-ing".
For those of you who don't EV train your pocket monsters, google or bing or search the technical explanation. For a super short and watered down version, defeating certain will earn you more stat points for the pokemon you're training. In the case of this comic, Luxray is EV training for Attack points, since that is what you earn when you defeat enough Gyarados-s.
It's a good thing that there are plenty of Gyarados-s in the game. I would hate for the that particular species of pokemon to die off just because they give off +2 in Attack stats.
I'm not sure if anyone will get the punch line since I didn't have enough room to draw more that two dead Gyarados-s in the final panel, the wording is kinda off, and that this idea was funnier in my mind back in the beginning.
Enjoy and stuff!