Gym Leader who killed you the most

[cookies kill you]

uhh lol never been killed before XD but its probably either Fatina Wake or Volkner probably Fatina as the hardest

[Demon Kitsune Yoko Kurama]

Maylene's Lucario

[Chrosion]

Well, none of them actually managed to make me black out. If you mean which one killed your Pokemon the most, then totally and epicly Volkner. It was a huge battle of Revives, Moomoo Milks, and frustration of the brain. .___. I don't remember how many though. And I have no idea why people think Fantina was so hard. I taught my Infernape Shadow Claw and it was all over. :P

[SkittyMoonStone]

Candice cause I kept Losing to her until I got Brave Bird(Finally) And I Smashed Frosslass in one hit

[CyberBlaziken]

Diamond : Fantina
Platinum : Candice

[Forretress Fan]

Platinum's Fantina. That Mismagius is evil. Especially when you do a playthrough w/o the Shinx evolutionary line

[kevin_durant35]

Diamond:Candice 6 times
Platinum: Maylene 4 times

If Lucius counts, then he takes the cake in Platinum with 14
Stupid Bronzong!

[Zoruagible]

Gardenia. It took me 5 tries when I chose Piplup

[Poetry]

Wake's Gyrados was a bit tricky for me as I had a horribly unbalanced team at the time and could only manage neutral hits which did almost nothing.
Thank god for critical hits.

[Jaguartail]

I would have to say Fantina. My teams are always weak against ghost types. Byron was hard as well, Bronzors are just plain annoying.

[Sceptrigon]

If I remember correctly, I lost to Candice the most because I didn't have Infernape or a good Pokemon to sweep with. I also struggled with Fantina a bit, but heck, I don't remember all that much.

[Royal_Qeca]

Candice was a hard to defeat. :/

[^Cutty^]

None. My team has never got butchered.
But the one who's more challenging, I gotta say. Yeah Fantina.

[InsaneDragoniteHD]

I have never found any of them hard ..so I say none.

[Kutie Pie]

Though I did not lose a single battle, Candice gave me a hard time (damn that Abomasnow and its evil laugh!) with Volkner coming in at a close second. Both were fun battles, though.

[Crasher]

Fantina consistently gives me trouble in each playthrough.

[PopPrincess_Lyra]

Uhm, none. I beat them all in my first try, nya~

[Doodlebug]

Uhm, none. I beat them all in my first try, nya~

Same here :P they were all easy

[Plus side down side]

I can't figure out why, but Maylene wipes the floor with me every time. It doesn't matter what team, or what circumstance, I have to reset. I never have any troubles with any Lucarios, except for hers! It drives me up the wall!

[sizida]

Fantina always put me in corners...

But I don't lose in any gym battles cause I always have items to back me up.

[Ferrin]

fantina's mismagius's psybeam and shadow ball.I was training monferno and meditite you can see why it was very tricky :£

[Klizcool]

Platinum- Wake destroyed me because My starter was an Infernape, and boy, was I in trouble! Luckily, I squeezed by (barely) by teaching him Thunder Punch. Next time though, I'm training a Shinx.

[empoleon49]

Th eonly gym leader I struggled with was Gardenia... That bloody Gardevior had me stuck at that gym for 2 days!

[Specter Vyle]

Fantina took me out quite a few times with that Magical Leaf Mismagius, but became victorious during a decisive battle using Torterra.

[Elysian]

I got raped by Wake....

Th eonly gym leader I struggled with was Gardenia... That bloody Gardevior had me stuck at that gym for 2 days!

I assume you mean Roserade?