My next update.
Returned to Undella Town and took the Marine Tube to Humilau. Beat Marlon and got the Wave Badge, after which Victoria the Fraxure evolved into Haxorus. The advantages of an Adamant Haxorus with near-maxed Attack EV's: 201 attack at Lv. 48!
Got the Colress MCHN from Colress on Route... 22 I think. Used it to awaken the Crustle in Seaside Cave. Got on the Plasma Frigate. Beat all the Plasmas and saw Kyurem. Chased Team Plasma to the Giant Chasm. Beat all the Plasmas, beat Colress. Met N, Zekrom, and Ghetsis. Beat Black Kyurem, and Ghetsis.
Headed west to the Pokemon League. Got through Victory Road and challenged the Elite Four. Easy peasy.
HALL OF FAME TEAM:
Victoria the Haxorus Lv. 60
Stephanie the Galvantula Lv. 60
Luna the Froslass Lv. 60
Michael the Arcanine Lv. 59
Chester the Feraligatr Lv. 59
Gordon the Abomasnow Lv. 59
Now, I wasn't sure if this was where the challenge ended, or if I had to continue playing until I beat Iris in the rematch. Just in case, I started doing the post-game stuff. Got through Clay Tunnel, Twist Mountain, that Route east of Nimbasa, and beat Alder. Now in the Black Tower.
Can somebody clarify for me if my challenge is over yet? Thanks
EDIT: Oh well, it doesn't matter anyways, because after extensive training in the Black Tower, I beat the Pokemon League's Lv. 72-78's and entered the Hall of Fame a second time. I'm Champion of the Favourites Challenge!