Bike north exactly 42784 steps, and you'll be in a Hall of Origin area. Save and reboot the system.
Continue biking north until the step counter reaches about 65,000 (Do NOT reset after rebooting). You will be in a fake sinnoh, walk anywhere version of the Hall of Origin.
You'll be in a mystery zone so do not save yet. Ride to the upper right corner of the area and bike west for about 65,000 steps. Eventually you will get to another fake sinnoh Hall of Origin in a Hall of Origin area.
Save and reboot in an area not on Arceus's platform or the stairs.
Go up the stairs.
Catch Arceus
Arceus, the final pokemon in the dex, has finally been discovered after months of searching! Below is a step by step guide to reaching Arceus through the void:
After you've gotten into the void through tweaking, save at the entrance of the poketech room.
(How to tweak the correct abyss video in video response section)
Walk down 1 step, then right 5 steps.
Reset step counter.
Run north about 429 steps or when you first get into a jubilife area. The area one step south should be turnback cave.
Walk west 10 steps, manual save and reboot the system.
Bike south 300 steps and save and reboot.
Bike south until you hit a wall with shadows behind it.
Take 1 step north, then reload the graphics by opening a full screen menu.
(If you don't take one step north, you will go into the turnback cave and will be able to get giratina if you haven't already, but thats not what we're going for.)
just need to remember this so im posting it in a old hardly played commented on game:
If Anyone Want's To Download A Music Only From Youtube Video ,Copy The URL Then Go To Google Write"Youtube TO Mp3"Then Pic The Secend One Then Past It Then Press (Convert )
 "Loved"){kind=icon}
 "Sacred Seasons 2 MMORPG"){kind=icon}
 "VVVVVV Demo"){kind=icon}
 "Sacred Seasons MMORPG"){kind=icon}
 "Defend your Honor!"){kind=icon}
 "I Remain"){kind=icon}
 "4 Differences"){kind=icon}
 "Level Up!"){kind=icon}
 "The Company of Myself"){kind=icon}
 "Alien Warrior"){kind=icon}
 "Allien Defence!!"){kind=icon}
 "Particles"){kind=icon}
 "( Ellipsis )"){kind=icon}
 "Scope"){kind=icon}
 "The Mouse 101"){kind=icon}
 "Grid16"){kind=icon}