You cannot find Latios in Pokemon HeartGold unless you went on wi-fi and got the Enigma Stone
Yes, Mewtwo, Latios and Latias will be in HeartGold and SoulSilver.
There is latios and groudon.
I don't think you can get Latios in Heartgold legitimately. I'm pretty sure you can only get Latios in Heartgold by using an action replay code, such as the Pokemon Modifier Code. You could also trade it over from Soulsilver, I think.
you can buy soulsilver and get it on there and trade it on to heartgold,get into the palpark or trade for it using wi-fi your best bet would be wi-fi
u can only get it on soul silver, the same way u get latias.
You have to fight it until its weak then use a master ball
You can find Latios on Pokemon Emerald, Ruby, and SoulSilver.
You can't get Latios in HeartGold. You can get Latias, to get her, talk to the copycat in Saffron and find her lost doll in Vermillion city at the fan club and Steven will be out there when you come out. He will talk about Latias for a minute and Latias will be in Kanto just walking around like Raikou.
Yes, when you beat the Elite Four and to the Kanto region you'll have to get a clefairy doll in Vermlilion City. When you walk out of the building you find the doll in (I think his name is Stephen) comes and tells you about Latios/Latias. And then you'll be able to catch it.
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.
The cool legendaries you can get in Soulsilver/heartgold are the following: Lugia, Ho-oh, Raikou, Entei, Suicune, Articuno, Moltres, Zapdos, Mewtwo, Latias, Latios (Latios in Soulsilver & Latias in Heartgold), Kyogre, Groudon, Rayquaza (Kyogre in Heartgold, Groudon in Soulsilver & Rayquaza if you have both).
Once you ask the Copycat in Saffron City to get her Clefairy Doll back Talk to the man inside The Pokemon Fan Club.Then he will give you the Clefairy Doll go outside.Then Steven Stone will talk to you he will say that Latias(HeartGold)or Latios(SoulSilver).Finally Latias or Latios will roam Johto or Kanto.But sorry,you can't get Latios without Cheating,Hacking or Trading. :(