Pokemon HeartGold SoulSilver Kanto Walkthrough Part 40 – Cinnabar City Gym

Well, this part is different. You need to head into the Seaform Islands. Just go up the ladder that you find inside to find the Gym!

For this Gym, you need to beat EVERY trainer to clear a path all the way to Blaine, the Gym Leader. First up is Scientist Lowell with his Arcanine lvl. 50. A simple start with opens up a path on the left and right.
To the right is Super Nerd Cary with his Torkal lvl. 53. It also leads on.
To the left is Scientist Daniel with their Ninetales lvl. 50 This is a dead on.

Further on to the right is Scientist Linden who sends out a Magmar lvl. 50.
Just past that, following the path Super Nerd Waldo who challenges you with a Numel lvl. 53. Follow the path and take on the next trainer. This last trainer is Super Nerd Merle with his Magcargo lvl. 53. This clears the way to Blaine. He tells you how he's persisted and had brought his Gym there to Seaform.

Blaine
Like fire, Blaine poses a short by intense battle. All his Pokemon know Overheat, a very powerful Fire-type attack. It may cause their Sp. Atk to drop, but all have a White Herb which counters this drop once. The Magcargo is moderately powerful, but has a serious weakness to water and ground type attacks. Magmar has some variety to it, with Thunderpunch, meant to give coverage to Water, but leaves it wide open to the other weaknesses that Fire has. The Rapidash poses a slightly different style of threat. While it is not the strongest, it is the fastest of Blaine's Pokemon. Strike with your own speedster and aim for a OHKO!

Full Restores: 3

Magcargo lvl. 54 – Overheat, Sunny Day, Smog, Rock Slide
Magmar lvl. 54 White Herb – Overheat, Sunny Day, Confuse Ray, Thunderpunch
Rapidash lvl. 59 White Herb – Overheat, Bounce, Flare Blitz, Quick Attack

He will award you with the Volcano Badge and TM 50, Overheat. With that taken care of, it's time to go back to Cinnabar and see about that final Gym Boss!