For me, it's Absol. Sure, it's too frail to get any real mileage out of its Pressure Ability, but its other Ability, Super Luck, can easily turn it into a monster, just because it gets both Night Slash and Psycho Cut! Two moves with a high critical-hit ratio + an Ability that raises its critical-hit ratio = critical hits left and right!

3010997
Kanghaskan

3011152 Yeah. But with its Mega Evolution and Parental Bond Ability that it gains from that Mega Evolution, it, Gengar, and Blaziken have suddenly become so powerful that they're now on the ban list.

3011179
lel, i take out a blaziken a day, what the fuck is the issue? of course i do it with excadrill

3011233 Mega Blaziken + Speed Boost = massive pwnage.

3011264
then kill it first. muh clawitzer tho

Absol and Kangaskhan (or however you spell it)

3010997 I'm gonna go with 2 Pokemon, and I'll say why.

First off is Dunsparce, who is STILL under-appreciated. Sure, it doesn't have the stats of a Blaziken or Steelix, but it has its own bit of charm to it. Serene Grace coupled with a great moveset (one of the best in the game in terms of variety) gives him a chance to be a great asset for your team.

My second is Mawile. Even before it got a mega evolution, it could still kick some serious ass. In this game, my moveset for her is Swords Dance, Iron Head, Play Rough, and Sucker Punch. In Gen V and below, you could interchange Play Rough with something like Crunch and still wreck shit. But now, with her Mega Evolution, she has the highest Attack stat in the entire game and people all of a sudden want her on their team. I can't tell you how many teams she's swept for me.

3010997 ChuckNorrischu, obviously.

In all seriousness, though, I wish Bayleef was more popular. It looks interesting, it has nice defensive stats and moves for a mid-evolved Starter, and I like the idea of the leaves that grow around its neck serving as antidepressants.

3010997 Steelix. Despite having a pretty impressive Defense stat it never really had a use on any team in game, until the Fairy type gym where it was the easiest to obtain and trade Steel type you could use for that gym. And then it got a Mega evolution in OR and AS, and it really started getting attention.