Pokémon HeartGold and SoulSilver were released in the same generation as Pokémon Diamond, Pearl, and Platinum. They contain the charm of the original games but added so much more. Remakes of Generation II, Pokémon HeartGold and SoulSilver are possibly the best games of the series. Using updated graphics and gameplay mechanics, they improve on the original games by more than a tenfold.

RELATED: Pokémon: 10 Unused Pokémon Designs That Look Better Than You'd Expect

HeartGold and SoulSilver take place across two regions and are enormous in scale. Naturally, Pokémon's developers have placed hidden secrets for players to discover. These are 10 things you never knew about HeartGold and SoulSilver.

Updated by Madison Lennon on February 29, 2020: Everyone is obsessed with Pokémon Sword and Shield right now, but devoted franchise fans still have a lot of love for many of the older games in the series. HeartGold and SoulSilver remain some of the most beloved games and are often considered some of the absolute best in the entire franchise.

We decided now would be a good time to revisit this list and update it with a few more secrets and things you can do in the game that you might not be aware of.

15 Get Your Photo Taken With A Gym Leader

One of the cool components of the HeartGold and SoulSilver games is the ability to get your photo taken in multiple places in the game by a photographer named Genzo.

There are a lot of different spots in the game where you can get your photo taken, but some of the most sought after ones are where you can get a picture with each of the gym leaders. Those opportunities are only available at certain times and locations, so you'll need to do some research to find out all the places.

14 Collect Shiny Leaves And Get A Shiny Crown

There is a very rare and special type of leaf you can get in the game that you will only find in rare places in the game. The only way you can find them is your Pokémon partner happens to pick one up.

While in a patch of grass, frequently talk to the Pokémon and see if they've found anything. It will take a lot of patience to find five shiny leaves, but then if you take them to Lyra or Ethan in New Bar Town, she will make a Shiny crown for you.

13 There Is Only One Place In The Game Where You Can Get A Sudowoodo

After you defeat Whitney, you'll be able to return to the annoying tree blocking the path on Route 36. Not many people realize that you can capture a Sudowoodo here, or if they do, they might not understand that it is the only chance you'll have in the game to capture it.

You need to get a squirt bottle from the Goldenrod flower shop and then use it on the tree. Doing so will trigger a battle between you and Sudowoodo, you may want to save before starting the fight in case you accidentally knock it out.

12 Catch The Legendary Hoenn Weather Pokémon

Did you know that you can catch the legendary Pokémon from the Hoenn region? Groudon, Kyogre, and Rayquaza are all available to find in the game, but it will take some major work to get them. First, you need to get all of the badges and beat Mr. Red. Afterward, you will have to get a Kanto starter from Oak and talk to Mr. Pokemon.

He will give you a special orb which you then take to the Embedded Tower and from there you can fight Groudon or Kyogre depending on the version of the game you're playing. For Raquaza, you have to get another orb and return to the tower.

11 It's Extremely Hard To Find A Copy Of Either Game

For some reason, there weren't as many print copies created of HeartGold and SoulSilver. Because of this, it is difficult to find a copy of the games now.

Even if you do, don't be surprised if they're priced extremely high at around $300 or more at online retailers like Amazon. Even on other sites like eBay, it's not much better. Most people price the games between $50 and $100 or more.

10 You Can Rematch The Elite Four (Different Pokémon)

You can rematch the Elite Four in Pokémon HeartGold and SoulSilver, over and over. It's recommended to do so since it's the most efficient way to level up your Pokémon. If you genuinely want to be a masterful trainer, rematch the Elite Four, again and again, until your Pokémon reach level 100.

This will make your Pokémon lineup powerful beyond your wildest imagination, making you unstoppable. The Elite Four trainers do not change, but the Pokémon they use in battle change the second time around.

9 Face Trainer Red

Trainer Red made his first appearance in the first generation of the Pokémon games. In this generation, players played as Red, a trainer from Pallet Town, who set out to become the world's most powerful trainer. He single-handedly defeated Team Rocket bringing balance to the Pokémon world.

In Pokémon HeartGold and SoulSilver, players can combat this masterful trainer by traveling to Mt. Silver. You have to defeat the Elite Four for him to appear. Red vanishes after being beat but returns every time after you beat the Elite Four.

8 Rematch Gym Leaders

It's possible to rematch the various Johto and Kanto gym leaders in Pokémon HeartGold and SoulSilver. In a multi-step process, players can find gym leaders for a rematch in the Fighting Dojo of Saffron City.

First, players have to obtain the phone numbers of gym leaders before calling them to the dojo. Phone numbers can only be obtained during certain times of the week. After being called, a gym leader will remain in the dojo until he or she is defeated. It's an excellent way to face a challenge and earn XP in the process.

7 Catch A Lapras In Union Cave

Union Cave is a cave appearing in the Johto region between Route 32 and Route 33. The cave is connected to the ocean, and it's found deep underground. Under the right circumstances, a wild Lapras can be captured in Union Cave.

PREVIOUSLY: 10 Confirmed Pokémon That Humans Eat

Come to Union Cave on a Friday (after defeating Morty), and you can encounter a majestic Lapras. You'll also need Surf to find and catch this Pokémon. According to Lapras's HeartGold Pokédex entry, "They have gentle hearts. Because they rarely fight, many have been caught. Their number has dwindled."

6 Receive A Free Eevee!

In addition to being able to purchase Eevees at the Celadon Game Corner for an outrageous price, players can obtain a free Eevee from Bill. Bill is the PC master who has helped players in various Pokémon games.

First, players have to find Bill Ecruteak City, then talk to him. He'll be standing in the city's Pokémon Center. After talking to him in Ecruteak City, Bill will travel to Goldenrod City. At Bill's house in Goldenrod City, he will be by a table with his family. Bill will give you a free Eevee if you speak to him here.

5 Catch Red Gyarados

Of the things mentioned on this listicle, catching a Red Gyarados has to be one of the easiest. It's not that catching a level 30 shiny Gyarados is easy because it's actually a big challenge. It's because reaching Red Gyarados is not that difficult in comparison to other tasks on this list.

Red Gyarados is found in the Lake of Rage, which is north of Mahogany Town. You'll need the technique Surf to get to this Pokémon and a team that can combat its power. Defeating Red Gyarados will cause it to disappear, so bring plenty of Poké Balls and save before facing it.

4 Catch Legendary Birds

Finding the legendary birds of the Kanto region is as easy as finding them in the original Pokémon games. Not much has changed since they were introduced in Pokémon HeartGold and SoulSilver, aside from a few small changes.

RELATED: Pokémon Sword & Shield: 5 Things That Make The Game Too Easy (& 5 That Keep It Challenging)

One thing that the three legendary birds have in common is that they must be found after collecting all 16 badges. Find Articuno in Seafoam Island, find Zapdos in the Power Plant, and find Moltres in Mt. Silver. Moltres is found in Victory Road in Generation I, which differs from Pokémon HeartGold and SoulSilver's Mt. Silver.

3 Find The Blue Flute In Viridian Forest

Although one can use the Pokégear to play the Poké Flute song on the radio, there is also something called a "Blue Flute." The Blute Flute can be used to awaken Pokémon in battle while the radio card cannot.

The Blue Flute is found in the Kanto region and is similar to the Poké Flute. Head to the beginning area of the Viridian Forest and you should find the Blue Flute laying on the ground. It awakens your Pokémon for free, so it beats using an Awakening item.

2 Obtain Hoenn Starter Pokémon In Saffron City

We love Pokémon HeartGold and SoulSilver because of the numerous Pokémon that can be caught. Pokémon Sword and Shield could learn a few things from this classic remake. In addition to finding the Kanto starters, players can discover Hoenn's starter Pokémon in the games. For your reference, Hoenn is the generation with Pokémon Emerald, Ruby, and Sapphire.

You'll have to choose of the three, but the fact you can get them is better than nothing. Go to Saffron City's Silph Co. building and talk to Steven Stone. He will offer three stones with each representing their respective Pokémon.

1 Obtain Kanto Starter Pokémon From Professor Oak

After you've obtained all 16 badges and beat Trainer Red, you can get one of three Kanto starters in the Kanto region. To get either Charmander, Bulbasaur, or Squirtle, you must talk to Professor Oak in Pallet Town after completing the previously mentioned tasks.

Who you choose is up to you. These Pokémon are some of the most impactful in existence. The fact you can get these Kanto starters in Pokémon HeartGold and SoulSilver is stupendous.

NEXT: Pokémon Sword & Shield: The 10 Most Shocking National Dex Cuts