It's not the "last" Legendary Pokemon that you can find in Pokemon HeartGold, but most people usually catch that one last given that you need to have both Kyogre and Groudon in your party for Professor Oak to give you the Jade Orb to get to Rayquaza.
In the pewter city museum. to get his attantion you must bring walking latias ( heartgold) or latios ( soulsilver ) with a soul dew from a mystery gift. then he will take you to saffron city. he will talk to you for a while. then he will go back to pewter then show you latios ( heartgold ) or latias ( soulsilver ) outside of the museum. then after you defeat or catch one of eon Pokemon that's the last of him.
Houndoom is not considered a legendary pokemon because it is easy to get multiple houndooms. Legendaries are generally pokemon that can only be caught once in any given game (and are also difficult to catch as well as usually among the last pokemon in the pokedex for a region).
GET THE LAST BADGE......
You can catch one of the three legendary dogs; Bulbasaur=Entei, Squirtle=Raikou, Charmander=Suicune. you can catch them in vermilion city, fly to vermilion city and go north, you can find them in the last rows of grasses in the upper part of vermilion,
You don't, the three 'crown' Legendary Beasts are obtained via a wi-fi event for SoulSilver/HeartGold.
First- Gotta Next- Catch em' Last- All! Gotta Catch em' All!
It's not the "last" Legendary Pokemon that you can find in Pokemon HeartGold, but most people usually catch that one last given that you need to have both Kyogre and Groudon in your party for Professor Oak to give you the Jade Orb to get to Rayquaza.
In the games that came before heartgold and soulsilver, I don't believe anything special happens. In Heartgold and Soulsilver, you can now catch the last 2 unown (the "!" and the "?") in the Hall Of The Ruins Of Alph. Then the scientist that gave you the unown recorder comes out and gives you a pat on the back...
One of the last things to do is battle Red at Mt. Silver. You can also try to catch the legendary bird Pokemon throughout Kanto. You could also catch the legendary dog Pokemon throughout Johto and Kanto.
In Pokemon Leafgreen or Firered, you should try and catch the one last legendary Pokemon with your master ball if you saved it. (It depends on your starter Pokemon on what legendary you can get.)
It's your opinion, but in HeartGold you can catch Ho-oh, Suicune, Raiku, and Entei, and in SoulSilver you can catch Lugia, Zapdos, Moltres, and Articuno. There are also more Pokemon available in HeartGold than SoulSilver. Edit: The person who last answered this question is wrong, you can catch all of the above Pokemon in both games, not in either or. I know this because I have soul silver and I have suicune, raiku, Entei, Ho-oh, Lugia, Zapdos, Moltres, and Articuno; so obviously you must be able to catch them in both.
Go in the bug catching contest in national park and by the entrance to the park on Tuesday talk to the door man and go the contest and you can only have the last one you catch and if you catch the Pokemon with the best health you win
Last time u could go to Toys 'r' us...... But now cannot unless cheat..........
It depends on what order you capture them in.After dialga and palkia the legendary Pokemon you can catch are :Regigigas,Giratina,Cresselia if you havent already Azelf,Uxie,Mesprit,Arceus,Darkrai,Rotom (not legendary but rare nat dex required) shaymin and heatran.
Moltres articuno zapdos raikou entei suicun rayquaza groudon kyogre ho oh and lugia and mewto and palkia dialga giratina and last but not least powerful legendary of all arceusgroudon
There r 2 pokemon that run ( like mesprit,aself,and ukie in diomend ) and u dont fly u run got it catch then