Gary is infamous in thePokemonfandom for always being one step ahead of the player.
Gary is arrogant, but likeably so.
The player character encounters and fights against Gary several times throughout his or her journey.

Nintendo
Every Pokemon trainer has favorites, though, and that includes Gary.
His lineup changes little throughoutPokemon Red/Blue,with one exception.
However, the next time you meet Gary, his Raticate is gone.
So what happened to Raticate?
What Happened, Indeed?
Some fans assume Garys in Pokemon Tower to visit the grave of his missing Pokemon his Raticate.
But if thats the case, how did Raticate die?
So, how about it?
Did Garys Raticate die as a result of a particularly rough battle?
Again, theres no easy yes or no answer, but its not very likely.
Instead, he says, What are you doing here?
Your Pokemon doesn’t look dead!
I can at least make them faint!
Lets go, pal!
By contrast, some of the other mourners in Pokemon Tower mention their dead Pokemon by name.
Admittedly, none of this explains why Raticate is absent from Garys roster.