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Get it? Whomp? Is a wall?
....Nevermind
Here's the Summary, AS. Have Fun.
Hack in a Regice when you reach Striaton City.
Get Regice to red health, then use it to solo the gym (all of it), in red health, no healing at all.
After beating a gym, you must remove two moveslots from one of your hero pokemon (hero being Mario, Toad, Peach, anyone 'nice' and not evil).
After beating a gym, throw out items worth P(2500 x Gym Number)
Beat the Second Gym with Regice under the same conditions.
At the Third Gym, put Regice in box, and hack in a Registeel with the same level as Regice (Registeel's moves are whtever it would naturally have at that level).
Use Registeel to survive 10 attacks (damaging or otherwise, as long as they don't miss) from the gym leader, Registeel must start at red health, no healing. Repeat for fourth Gym.
Repeat the moveslot loss and item throwout restrictions.
At the Fifth gym, replace Registeel with Regirock (level = Registeel's level, moves are whatevr it would naturally have).
Roll a six-sided die, numbering your party pokemon 1-6. Whichever one is rolled, dies. If (Regirock's level - dead pokemon's level > 10), roll again until another pokemon dies.
No restrictions for Regirock in the fifth and sixth gyms, but you must choose. Either continue on with the Regi challenges, or hack in a Vanguard when you reach the 7th gym (Vanguard follows the standard Vanguard restrictions when you hack him in, all other restrictions are void).
If not, then hack in Regigigas at gym 7.
You must solo the Gym with only one pokemon, with only one move. No switching moves even after switching out.
Solo Gym 8 under the same restrictions. You may use a pokemon other than the one you used for Gym 7.
At Victory Road, put party in box, withdraw Regirock, Registeel, Regice and Regigigas.
You may only have 15 items with you (don't throw them out, just make sure to use only 15 items or less).
Beat Victory Road with only the Regis. No going outside for anything, once you go in (except, obviously, whee you get to the exit).
That's it. Good luck.