First you need to catch the groudon, kyoger, and rayquaza from the cave near the safari zone. (To get groudon, kyoger, and rayquaza, u need the orbs from professor oak and mr. Pokemon). they have t obe original Pokemon from the cave. so u cant use Pokemon modifier to get them. I tested it out my self.
After u catch the three, go to professor Elm's lab and both of them will be talking together.
Yes you can get both Latias and Latios in Pokémon HeartGold however you'll need to have received an Enigma Stone key item from an official Nintendo event before you can find Latios in Pewter City directly outside of the museum and you will be able to come across Latias a roaming Pokémon that will only roam around the Kanto region but in order to get her to roam you will need to have exited the Pokémon Fan Club and talk with Steven Stone one of the Champions of the Hoenn region.
you need a silver wing
You do not need to show Rayquaza to anyone in HeartGold. In order to get Rayquaza, you need to show Kyogre and Groudon (from HeartGold and SoulSilver) to Professor Oak. In turn, he will give you the Green Orb. With the Green Orb in hand, you can find Rayquaza in the Embedded Tower.
You'll need to trade for it from Pokemon HeartGold.
You dont get Arceus in HeartGold. You need to trade one from another HeartGold or SoulSilver or trade one from the Sinnoh region games. WARNIG: IF YOU HAVE AN ARCEUS ON BLACK OR WHITE YOU CAN NOT TRADE IT BACK TO THE JOHTO OR SINNOH GAMES.
You need to get latias ( can only catch it on Pokemon heartgold) and latios (can only get it on Pokemon soulsilver) and speak to steven who is in the silph co. in saffron city.You must get the Enigma Stone from the WiFi event, which turns out to be the Soul Dew.
feh!you dont need action replay!just go to silph co. after you met steven stone several times,and talk to him,choose red stone,he'll give you torchic.
You need a Eevee and a water stone use the water stone on eevee! Simples!
Steven Stone will trade you a beldum in return for a Forretress (you need to evolve Pineco upto level 31) at the Silph co building, once you talk to him in the pewter city science museum)
2500 points
You'll need to evolve male Kirlia with a Dawn Stone.
You need to use a water stone. Steven Feagley
There is a shiny stone in nation park top right corner You will need rock climb to get
you need the fire stone... i think you canget at the bug catching contest.
In Pokeathalon, you need to get 3,000 points. But it will be available in some days.
You cant get you need to catch a jigglypuff and you give it a moon stone
No you do not need to catch Kyogre. You can get a Hoenn starter from a guy named Steven in Kanto.