Imagine that you have been hired to become a gym leader/elite four. You must have a team of one main type only, maybe with an extra pokemon of a different type added in there. What type would you choose, and what would your team be?
One main type only? Pssht. Bo-ring.
(If you really want to see my single-type team, take a look at this other question I answered this morning)
Personally, I think the whole single-type Gym deal is getting a bit old. I do believe Gyms should have unifying themes, and often a single type is a nice way of doing that, but I’d like to see some Gyms with more abstract themes, like the Viridian Gym of Heart Gold and Soul Silver, which is based around not a type but a move – Trick Room.
I, for instance, might build a Pokémon Gym based around the theme of night, using nocturnal Pokemon, and other Pokémon connected with darkness, or with the moon and the stars. This gives me an excuse to use my favourite Pokémon, the night-blooming Vileplume, as my signature Pokémon. I’ll assume my Gym is appearing somewhere in the mid-game and give myself three other Pokémon: Umbreon, Lunatone and Volbeat. Other trainers in the Gym, similarly, use Pokemon like Gloom, Clefairy, Gothorita, Lunatone and Solrock, Volbeat and Illumise, Ledian, Golbat, and Munna.
Every Gym needs a gimmick, of course, and here’s mine. All the rooms in my Gym are identical, and if you blunder straight through, you get turned around and wind up back at the start, as in the mazes the game sometimes throws at you like the Turnback Cave. The midnight-blue floor, however, is painted with glowing constellations, which you can use to find the correct path through the Gym. You can learn how to interpret the constellations by reading the books in the lobby and talking to the trainers in the Gym. A bit of good old-fashioned puzzle-solving – always good in a Pokémon Gym, right?