Game Freak's Pokemon Diamond, Pearl, and Platinum were extremely innovative in new methods for completing your Pokedex. From new evolution mechanics, legacy evolutions, new wild encounter methods, and more, the Generation IV games ushered in a new era of interesting Dex completion. But, which Pokemon are the hardest to obtain?

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With honey tree randomization, low catch rates, roaming legendaries, event-exclusives, old game requirements, and version exclusives, completing your Sinnoh Dex can be much more difficult than earlier (or sometimes, later) generations. Here's a list of the most difficult 'mons to capture, ranked from easiest to hardest.

Updated on March 1, 2021 by Michael Christopher: Remakes for the Generation IV games have been announced, titled Brilliant Diamond and Shining Pearl. With the reinvigorated hype for everything Sinnoh, we thought it would be a good idea to look back and remember some of the hardest Pokemon to find in the region. We've updated this list to celebrate the return to the Sinnoh region in style. 

15 All Forms of Wormadam

wormadam mothim burmy

Generation IV is the point in time when Game Freak really started exploring different forms for Pokemon. One of the Pokemon that received multiple forms was Burmy, a Bug-type Pokemon that resembles a bagworm. Burmy has three different forms, called "cloaks," that change based on where it battled last: Plant Cloak, Sandy Cloak, and Trash Cloak.

Female Burmy will evolve into Wormadam, and the cloak the Burmy has when it evolves become permanent on the Wormadam. Getting all three forms of Wormadam can be quite the task, as it's sometimes hard to find a person or wild Pokemon to battle on the right terrain to change the Burmy's cloak. Trash Cloak can be particularly annoying, as Burmy needs to battle in a building. If you've already defeated all the gyms, it can be tedious to find someone to battle.

14 Dual-Slot Exclusives

sableye

As the first Pokemon games on the Nintendo DS, Diamond, Pearl, and Platinum had an interesting mechanic contained within their coding. The Dual-Slot mode allows players to find different Pokemon based on which GameBoy Advance game is inserted in the bottom slot of the DS.

This means you can insert Ruby, Sapphire, Emerald, FireRed, or LeafGreen and different Pokemon will appear in certain areas. For example, if you have Sapphire inserted, you can find Sableye on Iron Island. If you have LeafGreen inserted, you may find Sandshrew in Wayward Cave. Since these Pokemon are exclusive to the Dual-Slot mechanic, it can be rather hard to get all of them.

On top of this, the Dual-Slot-exclusive Pokemon don't have fantastic encounter rates.

13 Spiritomb

spiritomb sword and shield

Every so often, the makers of Pokemon take a particular 'mon and make it extremely tedious to find. Spiritomb is one of these Pokemon. In the Gen IV games, you'll need to complete a series of steps to make this ghostly spirit Pokemon appear.

First, find an Odd Keystone. A karate fighter on Route 208 will gift you one, one can be found hidden in Twinleaf Town, or you can find them very rarely in the Sinnoh Underground.

Next, head to Route 209, where you'll find the Hallowed Tower. Place the Odd Keystone in it. Then, connect to local wireless and head to the Sinnoh Undergound. Speak to other players here 32 times — yes, you read that right. After this is done, head back to the Hallowed Tower and press A, and Spiritomb will appear.

Due to the fact that you have to interact with other players (it can be the same player, but one of you has to exit and reenter the Underground each time) and find a specific item, Spiritomb is easily one of the most frustrating and time-consuming encounters in series history.

12 Riolu

Riolu stomping on the ground in the Pokemon Anime

Lucario is a fan-favorite Pokemon, and also a pretty powerful one to use on your team, so it's understandable that many would look to find one in the Sinnoh region during a Gen IV playthrough. Unfortunately, there's only one way to get one.

You'll need to take a boat from Canalave City to Iron Island and find a man named Riley. Help him with a task and he'll reward you with an egg, but only if you have an empty slot in your party, which you won't have known when you left Canalave as the game doesn't tell you.

This egg will hatch into the only Riolu you can get in the game. Level it up with high friendship during the day and it'll evolve into Lucario. You can, of course, breed more, but this is the only way to get your first one.

11 Version Exclusives And Additional Starters

Every Pokemon generation comes with some version exclusives — species that can only be caught in one game or the other, in this case in Diamond or Pearl, but not both. Pokemon exclusive to Diamond include Seel, Scyther, Murkrow, Larvitar, and several others, while Pearl gets access to Slowpoke, Pinsir, Houndour, Bagon, Misdreavus, and others.

Starter Pokemon will also require you to have a friend or a second game. You only get to choose one of Piplup, Turtwig, or Chimchar. To complete your Pokedex, you'll need to gain both the other two starters and the version exclusives of the opposite game by trading your friend (or yourself).

10 Legendaries

Legendary Pokemon have always had low catch rates, meaning there's a good chance they'll break out of most of the balls you throw at them. It can often be a long, tedious grind of lowering health, inflicting sleep and paralysis, and throwing ultra ball after ultra ball until you finally add that single Dex entry.

Diamond & Pearl are no exception to this. Dialga and Palkia, the mascots (more version exclusives — groan), Heatran, Cresselia, The Lake Trio, and a few others round out one of the longest lists of legendaries in series history. Attempting to catch the entire list will take quite a few balls, so start saving.

9 Beldum

beldum

This tiny metal friend has always had a reputation for being a difficult catch. For whatever reason, the Pokemon Company and Game Freak decided to give it an extremely low catch rate. In most games, including the Generation IV games, Beldum has a measly catch rate of 3.

This puts it on par with most legendaries, including Mewtwo and Giratina. It can be an infuriating night of grinding when trying to catch this difficult 'mon. Luckily, it has a high spawn rate, so if you get too frustrated with one, you can knock it out and try again, releasing some anger in the process.

8 Vespiquen

Pokemon Diamond Pearl Honey Tree Pair
Pokemon Diamond Pearl Honey Tree

While this buzzy bee is not available in the wild, its pre-evolution, Combee, is. However, Vespiquen can be extremely difficult to obtain for a few reasons. The first is that it only evolves from female Combee. The gender ratio of these Pokemon is also incredibly imbalanced, with 87.5% of them being male, making it already difficult to find a female.

Add to this that Combee can only be caught with the sometimes infuriating honey tree method, where the player must slather honey on the 21 trees around the Sinnoh region. You must then wait 6 hours (real-time) for a Pokemon to appear, and it does not have a 100% chance of being Combee. If it is, you then only have a 12.5% chance of it being female. As a result, Vespiquen can often seem difficult to obtain.

7 Mesprit And Cresselia

Ah, roaming legendaries. This mechanic has provided a ton of stress to countless trainers over the years. Starting in Gold & Silver with the legendary beasts, this system makes certain Pokemon "roam" around the region, appearing on a different route or area every time the player goes through a transition screen between areas.

Trying to track down these Pokemon can be enraging if they constantly move away from you. Add to this the fact that they will often run on the first move, and it can be quite the process to hunt them down. In Diamond & Pearl, Cresselia and Mesprit utilize this mechanic, eluding the player as often as possible.

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5 Kangaskhan

Remember when older generations of Pokemon had designated Safari Zones? If you don't, they were basically a mini-area that allowed you to catch rare Pokemon within a certain set of rules. Often these zones would contain Pokemon that couldn't be found anywhere else. One of these areas was Diamond, Pearl, and Platinum's Great Marsh.

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In the Great Marsh, there's a set of binoculars that can be used to see which 'special' spawns would appear in certain sections. These sections would rotate daily. One of the Pokemon that could only be caught as part of these special spawns was Kangaskhan, and if it wasn't there, you'd have to wait another day to check again. It's probablet that you can see where this would go: frustration and impatience. Oh — and the binoculars cost 100 Pokedollars to use.

4 Regigigas

The leader of the Legendary Golems is a beast with a widely-hated ability, but is still necessary for a full Pokedex. There are two methods to catch this 'mon, both of which are difficult and annoying.

The first way to find this golem is now no longer accessible, being through a special event. Now, players looking to fill a Sinnoh Dex will need to import Registeel, Regice, and Regirock from their Ruby, Sapphire, or Emerald games. Any trainer worth their salt knows that catching the three titans in those games is frustrating enough. Once they're imported to the Gen IV games, Regigigas can be accessed (albeit with a tough fight and low catch rate, too).

3 Feebas

feebas

Feebas, Feebas, Feebas, oh how you allude us. This terrible fish is always a nuisance. It's a nuisance to find, it's a nuisance to catch, and it's a nuisance to evolve. In every game, Feebas proves to be one of the most hair-pulling, frustrating 'mons to find. This remains true in Diamond, Pearl, and Platinum, where this funny fish can only be found on four daily-rotating tiles in Mt. Coronet.

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This can be an extremely tedious and lengthy hunt, and if you don't find it in time, the tiles will rotate and you'll have to start all over again. Add in the fact that it can only evolve by increasing its Beauty condition, which is no easy feat itself, and you've got a real tough one on your list.

2 Manaphy And Phione

Manaphy and Phione, while definitely cute and not the worst Pokemon in the world, are widely disliked, if you take internet forums to heart. These two, who are in the same evolution family (maybe? It's unclear), but don't evolve into each other (cue confusion), are pretty difficult to get your hands on.

If you're looking to fill your dex, you'll need a copy of Pokemon Ranger. From there, you'll have to unlock a special mission with a code, rescue an egg, and then port it over to your Diamond, Pearl, or Platinum cartridge. You'll hatch a Manaphy from the egg, who you will then need to breed with a Ditto to obtain Phione. This method is strange and annoying, which may explain why they're disliked.

1 Munchlax

munchlax

This little monster may be at the top of the list for the hardest Pokemon to catch, regardless of region or generation. Munchlax, the baby pre-evolution of Snorlax, defines frustration for many Pokemon players.

Remember Vespiquen and the honey trees? You'll be revisiting them for this little guy. Slather your honey, wait six hours, and repeat until you find Munchlax. Here's the catch, though: Munchlax will only be possible as a spawn at 4 of the 21 trees (based on your trainer ID and other factors), and it only has a 1% spawn rate. Put on an audiobook, get some coffee, and start hunting.

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