Pokémon FireRed and LeafGreen/Seven Island

'Seven Island is the last of the Sevii Islands, and holder of the strongest trainers of the game, aside from the Elite Four. Gear up and tackle the challenges within Trainer Tower, and make your way to solve the final puzzle within the Tanoby Ruins!'

Seven Island Town


Seven Island is the last of the Sevii Islands. The town offers the usual amenities, such as the Poke Center and Poke Mart. A Move Tutor on the bridge south of the town will teach one of your Pokemon.

There are two paths you can take. Head north and you'll encounter Trainer Tower. Head south and you'll go towards Sevault Canyon and the Tanoby Ruins. You can tackle them in whatever way you choose.

Trainer Tower


Trainer Tower is the ultimate trainer challenge. Should you choose to climb it, you will have to go through eight levels of trainers to reach the top and claim a special prize.

Battling the trainers here will neither give you levels nor money. The battles are timed, so try to do your best, and the level of the Pokémon here will match the level of your highest level Pokémon.

There are 4 modes: Single Mode, Double Mode, Knockout Mode, and Mixed Mode.

Entrance
Heading north, you'll have to tackle two battles before you enter the Tower. Within, you'll find a Poke Center and a Poke Mart as well. The battles are unlike other challenges you may have found in different Pokemon games, as you are allowed to heal within and outside battles. Good Luck!

Single Mode
Single Mode are simply single trainer battles. Beat the eight trainers and you'll be rewarded with an Upgrade (to evolve into  during a trade).

Double Mode
Doubles are battles with couple trainers. Beat eight couples and be rewarded with a Dragon Scale (to evolve into  during a trade).

Knockout Mode
Knockout Mode are battles where you will tackle three trainers, one after the other with no healing time between battles. Beat eight floors and be rewarded with a Metal Coat (to evolve and  into  and  during trade respectively. It also powers Steel type moves when held).

Mixed Mode
Mixed brings a combination of all the previous modes. Beat eight floors and be rewarded with a King's Rock (to evolve and  into  and  during trade respectively. Also a Pokemon holding it will now have a chance to make the opponent flinch when attacking).

Canyon Entrance
Following the road south you'll find the entry zone towards Sevault Canyon. Canyon Entrance is a small zone mostly covered in tall grass, but you can also find challenging trainers here, so you may want to spend some time leveling your Pokemon here.

From the middle of the zone, head south and east to continue on, the other path is a dead end.

Items

 * Rawst Berry (hidden): dead end road at the west side

Sevault Canyon
Here you will find the strongest common trainers in the game, so it's a great place to train. There are a couple of useful items that you can find throughout the road (King's Rock requires Strength and Rock Break).

Head further south and enter the Tanoby Ruins. Solving the earlier puzzle allows you to capture Unown within these ruins! I know, a crappy reward for all the struggles you went through, but at least, you have finished exploring the Sevii Islands! Head back to Victory Road. The Elite Four are ready for a rematch and are waiting for you!