Page 1 – Arceus | Articuno | Azelf | Celebi | Cresselia
Page 2 – Darkrai | Deoxys | Dialga | Entei | Giratina
Page 3 – Groudon | Heatran | Ho-Oh | Jirachi | Kyogre
Page 4 – Latias | Latios | Lugia | Manaphy | Mesprit
Page 5 – Mew | Mewtwo | Moltres | Palkia | Phione
Page 6 – Raikou | Rayquaza | Regice | Regigigas | Regirock
Page 7 – Registeel | Shaymin | Suicune | Uxie | Zapdos 

Darkrai

This Dark-type Pokemon’s signature move is Dark Void, which induces sleep on its opponent. With Darkrai’s Bad Dreams ability, the sleeping opponent loses health every turn.

Pokemon Diamond / Pearl / Platinum – By event only. When trading, look for a Darkrai in a Cherish ball, with OTs like ALAMOS or えいがかん.

Trivia: Darkrai is the only Dark-type legendary, and is the only Pokemon who can learn the move Dark Void.

This unique DNA Pokemon is the first  legendary Pokemon to be able to morph into different forms with different sprites and stats.

Deoxys is available by event only. It’s been given away quite a bit, so you shouldn’t have a problem tracking one down from a reputable source. Look for OTs like 10th, Gamestp (from the most recent North American Deoxys giveaway at Gamestop), OT Caught, DOEL, or SPACE C.

Trivia: Deoxys is the only Pokemon to yield varying EVs, depending on its form.

Dialga

The cover star of Pokemon Diamond, this Steel/Dragon type’s powers are amplified with the use of an Adamant Orb.

Obtainable via:

Pokemon Diamond – If you’re playing through Diamond, Dialga is a total no-brainer since you must encounter it as part of the plot. When you finally make it through Mt. Coronet, after your big boss battle with Cyrus, Dialga will be waiting for you to battle and capture. After you capture it, make sure you walk past where it was standing and pick up the Adamant Orb, which is an essential hold item to maximize Dialga’s power.

Pokemon Platinum – Dialga will be at Spear Pillar, but you won’t be able to battle it until you’ve obtained the National Dex and returned to Spear Pillar after your initial encounter there with Cyrus and Giratina.

Note that you’ll encounter Dialga at level 47 in Diamond, and an impressive level 70 in Platinum.

Trivia: Dialga has the most type resistances out of any legendary Pokemon, with 11 resistances (Bug, Dark, Electric, Flying, Ghost, Grass, Normal, Psychic, Rock, Steel and Water) and one immunity (Poison).

Entei is the Fire type third of the legendary beast trio introduced in Pokemon Gold/Silver.

Obtainable via:

Pokemon Colosseum – Entei is available to capture during the boss battle with Cipher Admin Dakim at Mt. Battle. Make sure you have a Water type Pokemon with you, as most of the trainers here use Rock and Ground types.

Pokemon FireRed / LeafGreen – If you chose Bulbasaur as your starter Pokemon, Entei will appear roaming around Kanto after you beat the Elite 4.

Entei knows the move Roar, which allows it to flee battle regardless of whether you used Mean Look or any move/ability that prevents fleeing, so don’t even try it. Warning: under no circumstances do you want him to use Roar!  If he flees using Roar he’ll be gone… forever! If you insist on going after him without using a Master Ball, be aware that it’ll probably take several encounters before you finally get him.

Entei is an excellent candidate for using your Master Ball. Actually, it is THE candidate for the Master Ball – do yourself a favor and just use it, please. 

Trivia: Entei’s sprite has gone through many changes since it was introduced in Gold / Silver, starting with a bright red color and then switching to brown in later games.
 

Giratina

This Ghost/Dragon type Pokemon has two distinct forms – its Altered Forme which appears in Diamond and Pearl, and its Origin Forme, which is shown on the cover of Platinum. To be in its Origin Forme (which is only available in the Platinum version), Giratina must either be in the Distortion World or be holding the Griseous Orb.

Obtainable via:

Pokemon Diamond / Pearl – After obtaining the National Dex, head to Route 214 (Fly to Veilstone City and go south). You’ll need Surf, Rock Smash and Rock Climb. Head south down the path, and looking along the eastern side (to the right) you’ll see an opening that wasn’t there before. Head inside and you’ll be in Sendoff Spring. Go down the path, up the hill using Rock Climb, and across the spring using Surf to enter Turnback Cave. Turnback Cave is kind of a huge foggy maze. There’s a riddle on the pillar when you enter that says you must find 3 other pillars within 30 rooms, and Giratina will appear. It’s not too difficult to find through trial and error, but the quickest way to get there is:

From the entrance, go NORTH, NORTH, EAST, EAST, EAST, EAST, EAST, EAST.

So, just go north twice and then east until you get to the room with Giratina in it. Our Diamond/Pearl advanced guide has a detailed strategy for catching Giratina, which you can view here.

Pokemon Platinum – While Giratina is at level 70 in Diamond and Pearl, the Giratina you’ll find in Platinum is a mere level 47. Finding Giratina in Platinum is a no-brainer because you’ll have to trigger the encounter at some point if you’re playing through the game. Once you get to Spear Pillar at the top of Mt Coronet, after the boss battle, instead of battling either Dialga or Palkia, you’ll enter a portal into the Distortion World. It’s not that big of a place, so you should be able to navigate your way through until you reach Cyrus. After you defeat him, Giratina will appear and you’ll be able to battle it.

Trivia: Not only is Giratina the only Ghost type legendary, it’s the only dual-type Ghost/Dragon Pokemon.