First I decided to breed myself an Illumise with its Hidden Ability, Prankster, and a Corphish with that one's, Adaptability, along with an Oddish. Then I caught an Eevee which I evolved into a Glaceon, a Sandslash, and a Tynamo that I got into an Eelektross. Once they were all EV'd up and Level 70, I named them Lighter, Viscerala, Hula Lady, PrttyChill (would have been "Pretty Chill" if this was Generation VI), Dune Rover, and Corrosion, respectively.
After I decided on what moves to enter with, it was time for action!
I decided to begin with Grimsley. First time I lost because I got greedy and tried to win without any items. Then we went for it again.
He began with Honchkrow as I used Corrosion first. He used Night Slash for over a third, while my Spark almost killed him. He healed, allowing me to use Coil. Then he used Psychic, bringing me below half but I finished him with one.
Then Krookodile came next. He Intimidated off my boost, and he used Crunch which I barely lived, then Drain Punch did less than half. I went to Viscerala and ate a Crunch, only for him to lower my Defense. So I went to Hula Lady and ate an Earthquake, then Crunch left me below a third before Giga Drain finished him.
Houndoom came after, so I switched to PrttyChill and was OHKO'ed with Fire Blast. Then I went to Viscerala again and barely lived a Fire Blast, allowing me to go for Crabhammer and kill him.
Scrafty came after, and I used Endeavor to get him to 18 HP before he killed me. I went to Lighter, and used Charm as I was unsure about whether he healed or not, and he had, so I cut his Attack before he did 2/3 my health with Head Smash.
Tyranitar came afterwards, and I used Charm then he missed with Stone Edge. Bug Buzz didn't do much, then he killed me. I used Dune Rover next, and he missed with Dark Pulse (haha, your own ability screwed you over) and I killed him from 3/4 with Earthquake.
Bisharp was last, and his Night Slash did less 1/3 while my Earthquake was an OHKO.
I decided to go for Caitlin next.
I started with PrttyChill as she used Musharna. My Ice Beam did less than half, and I stayed asleep for two turns but somehow woke up on when it had 3 HP and beat her with two more Ice Beams.
Alakazam came afterward and killed with a Focus Blast (with a critical hit, too). I went for Corrosion next and Psychic did over half, while my Crunch left her with 1 HP but got the Defense drop, so she wasted her Full Restore as I killed her.
Metagross came afterwards. Zen Headbutt beat me from over half. I went for Hula Lady, and she used Zen Headbutt for 2/3 while I safely hit with Sleep Powder. Then I went to Dune Rover. She continued to snooze, and Earthquake killed her from 4/5 her health.
Gallade came next, and Leaf Blade did over half, but so did my Shadow Claw, before she killed me with another. I went to Lighter and used Encore, locking her into that move, but she did over half with a critical hit. But that allowed me to go for Charm, and she was down to -4 when her encore ended. I went for one more Charm and got her to -6, then she used Psycho Cut and I encored her into that. I went to Viscerala and she stayed in (why does this not surprise me?), allowing me to use Dragon Dance. Then a Night Slash killed her.
Reuniclus and Gothitelle were both OHKO'ed with Night Slash.
Then we had our sights on Shauntal.
I began with PrttyChill against Cofagrigus. Ice Beam did well over half, but she burned me with Will-O-Wisp. Even with that, Icy Wind finished her.
Gengar was next. I switched Corrosion into a Focus Blast, only for it to miss. Then she used Sludge Bomb, which did so tiny under half, and my Crunch did almost 3/4 her health. She didn't heal, allowing me to survive in the red before killing her with Spark.
We had Golurk after that, and Stone Edge finished that off. I went to Hula Lady, and she took a Hammer Arm for less than half before I used Sunny Day. I used Giga Drain to get some health back, and it got her around 1/3. She used Hammer Arm again, and I took more than last time but another Giga Drain beat her and got me over 2/3.
Froslass was next, to my surprise. I used Giga Drain, which didn't even do more than half, as she missed with Blizzard. I hit with Sleep Powder just in time for the sunlight to fade. She snoozed and I used Sunny Day again, then I went for SolarBeam and finished her off.
Chandelure came next, and she was still faster, even with Chlorophyll, and killed me with Fire Blast. I went to Lighter and got in a Thunder Wave, and she got fully paralyzed. Nice! I used Bug Buzz just to stall for time before she killed me with another Fire Blast. Then the sunlight faded, and I went to Viscerala and killed her with Crabhammer.
Drifblim was last. She used Thunder and killed me. I went to PrttyChill, and survived a Shadow Ball taking only 1/3 my total health (and getting a Special Defense drop) before I OHKO'ed her with Ice Beam.
Last up was Marshal. I was rather concerned about this fight, but I decided to go for it and think cleverly. Couldn't make it first try, though. As for the second?
I started with Dune Rover against his Throh. I began with a Swords Dance as he used Payback for around a quarter of my health. Then I used Earthquake for 4/5 as he used Payback again. That one got a critical hit and knocked me near 1/3. He healed, as I 2HKO'ed with Bulldoze followed by Earthquake, and gained HP from the Shell Bell and got just above half.
Mienshao was afterwards, and he used Fake Out. Not wanting to lose my defenses so soon, I switched to Viscerala as he used Hi Jump Kick…but missed, and took half his health. Then he hit next turn. I went to Corrosion and took a Hi Jump Kick for over 2/3 my health, as I killed him.
Conkeldurr came next, and was faster and killed me with Stone Edge before he was burned with the Flame Orb. Despite sounding like a very inane idea, I went for PrttyChill. I set up a Barrier, as his Hammer Arm did a quarter of my health. Then I used Ice Beam for over half his and was knocked below half. Icy Wind killed him while he was in the red.
Sawk was afterwards, and he hit with Close Combat, scoring a critical hit that I doubt it even needed (I was below half). I went for Hula Lady, and he used Close Combat once more, for almost 2/3 my health, before I used Sunny Day. Giga Drain didn't even kill him from -2, and I lived another hit with 16 HP. Another Giga Drain killed him.
Machamp was afterwards, and after some heavy thinking, I decided to use Sleep Powder.
Which hit. Then I went for SolarBeam and did over half…but he woke up on the first turn and killed me. I went for Dune Rover and managed to kill him from 40% or so with Earthquake.
Lucario was last up, and this was scary. I went back to Lighter, and he used Dragon Pulse for 69 HP (lol). He used ExtremeSpeed for over half my remaining health, but I survived and got in a Thunder Wave. Then he killed me with another ExtremeSpeed. I only had Dune Rover left, who was just below half. Earthquake was an OHKO, winning me the fight.
Lastly we had the Champion, Iris. This was going to be a scary fight, so unlike the Elite Four, I decided to allow item usage for it.
She began with Hydreigon, as I started with Corrosion. She used Dragon Pulse for a tiny bit less than 2/3 my health, allowing me to paralyze her with Thunder Wave. I got in Drain Punch for less than half, and she used Fire Blast and beat me even after I was healed between that and Leftovers (must've been a min/max damage thing). I went to PrttyChill and finished her from 5/8 or so with Ice Beam.
Then she went to Aggron. I went to Dune Rover and took a Head Smash for a hair over 1/3 my health despite resistance, and I used Earthquake which left her with 1 HP (had I put on the Soft Sand again and not the Shell Bell it would've killed), and she used Autotomize. Then she healed, and I left her at 1 HP yet again. She used Double-Edge before I finished her with Rock Slide and gained 1 HP from the Shell Bell. I had over half my health afterwards.
Then she came to Lapras, who was faster and wiped me with Blizzard. I went for Hula Lady, and she hit with Sing. Then I survived her Blizzard with 2 HP (!!!!!!!) and woke up, so I used Sunny Day. Then I hit with Sleep Powder, and after juggling between decisions on what to do I used Giga Drain, which did less than half even with the Meadow Plate, and she woke up first turn and used Hydro Pump, which got me back into the red (fuck this stupid critical music!!!). Then I used SolarBeam and killed her, with a critical hit that most likely didn't matter, but it could have.
Salamence was next up. I decided to use a Max Revive on Corrosion before she used Crunch and the sunlight faded. I went to Lighter and used Thunder Wave before she got in Fire Blast and OHKO'ed me. Once again, PrttyChill hopped in to the rescue and killed her with Ice Beam.
Then she came to Archeops, and thinking it would be too impractical to stay in, I switched to Corrosion who was promptly met with a critical hit Stone Edge. I went to Viscerala, and she used Stone Edge but I managed to survive it with just over 1/4 my health, and I went for Dragon Dance, thinking I could just kill her with Crabhammer and then use Endeavor on Haxorus. Right?
WRONG! She was still faster even after that boost, and killed me with Dragon Claw. I went to PrttyChill, and revived Dune Rover before she used Stone Edge and got yet another critical hit, so it may or may not have mattered. I went to Dune Rover and revived Hula Lady as she used Acrobatics, which triggered her Flying Gem and killed me. Then I went to Hula Lady and used a Max Revive on Dune Rover, since I felt he had enough defense to take a hit at full so I could use another revive, before she used another Acrobatics. Dune Rover was back out, and I revived Lighter as another Acrobatics from her did a hair over half my health. Then I revived Corrosion before she killed me. I went to Lighter, and used Thunder Wave before she beat me with Acrobatics. Next was Corrosion's turn to be fodder as I revived Viscerala and she got fully paralyzed. I revived Lighter in preparation for Haxorus before she killed me with another Stone Edge. Viscerala was up, and I used Crabhammer. Which missed. And she got fully paralyzed. WOW, that was something funny. I hit with it next turn, and it OHKO'ed, sure enough.
Haxorus was last up. I decided to revive PrttyChill as she used Outrage, then I went to Lighter and paralyzed her with Thunder Wave before she hit with another Outrage. I went to PrttyChill, who was the only one I had left, and just for good measure I decided to use a Max Revive on Dune Rover…and she hit herself in confusion! That allowed me to finish her with an Ice Beam from 90% or so, winning us the fight. Whew!
So we were taken into the Hall of Fame and inducted as Champions!