Pokémon - You'll only know true rage when you find that one klefki

To answer your questions:
1. Yes, it is about competitive klefki

What make this Key ring the one of the most annoying opponent you will ever face. Let get right to it:

1. One of Klefki's abilities is Prankster. Prankster gives +1 priority to status moves.
2. Swagger: If an opponent use swagger against you, your pokemon will gain +2 attack but will get confused as well, remember that the damage that confusion does to your pokemon (if you hit yourself) is based on your Attack.
2. Substitude: Klefki pay a 25% HP fee to have a little doll take the damage for him. Paired with leftovers, he will gain the hp back in about 3 turns if you don't manage to break throw confusion.

3.Thunder Wave: Surprise! Not only you are confused, you are also paralyzed! So now you have to hope you break throw paralyze AND confusion

4. Reflect; Light screen: Cuts in half the damage that klefki may take for 5 turns. Simple as that. Light screen reduce Special attack, reflect reduce physical.

5. Foul Play, although I didn't add that to the picture, If klefki uses Foul Play, The attack used in the damage calculation will be of your pokemon, who had his attack doubled. Since you are paralyzed, klefki will outspeed your pokemon.

You see that all those moves (except Foul Play) are status move, therefore, it doesn't matter how fast your garchomp is, klefki got priority, so he will move first.

I believe this might be appropriate :