(left: pre-E4, right: post-E4)
Empoleon Lv 66
Flash Cannon/Charm/Surf/Ice Beam
Solid starter and always there to carry me through a fight if needed, though mostly stayed back to soak up experience outside of major fights or when I wanted to finish something quickly. Mostly had Quick Claw because I like to see it proc.
Bibarel Lv 49
Strength/Surf/Yawn/Crunch
Surprisingly strong through the midgame with access to solid moves and one of my Amulet Coiners of choice. Note that it was actually on par with Staraptor and Luxray since I used them around the same parties, but they leveled ahead during the E4.
Staraptor Lv 54
Quick Attack/Close Combat/U-turn/Brave Bird
Had good stats but not great (STAB) moves for a while until picking up Brave Bird right at the penultimate rival battle.
Luxray Lv 55
Spark/Volt Switch/Thunder Wave/Bite
The most extreme example of a good stat, bad learnset mon that suffered. I still had Tackle until I replaced it with Thunder Wave near endgame. It still handled route trainers well enough though.
Kricketune Lv 48
Night Slash/Slash/X-Scissor/Fury Cutter
Pretty much a glass cannon but a good one. No one beats the bug.
Golem Lv 47
Earthquake/Explosion/Rollout/Rock Blast
Good bulky rock. I didn't use it that much but it thrives in its good matchups.
Machamp Lv 40
Low Kick/Low Sweep/Strength/Knock Off
The attack was high but there weren't much convenient matchups for it other than Byron and caves and it is slow and not really that defensive.
Pachirisu Lv 51
Thunderbolt/Nuzzle/Super Fang/Charm
Mainly there for Pickup utility but had surprisingly alright performance.
Jirachi Lv 54
Meteor Mash/Thunderbolt/Dazzling Gleam/Psychic
I mostly held it back with a natural learnset because its stats were high enough, then sent a couple Veilstone TMs around Surf, and it picked up Meteor Mash and Psychic naturally in the endgame. Solid all rounder though it had less to do in the E4 than I thought.
Beautifly Lv 39
Stun Spore/Giga Drain/Bug Buzz/Air Cutter
Picked it up in Eterna Forest as a Level 12 Beautifly, which serebii was the only site I found to have its accurate learnset for. The patch change giving it Wurmple's Bug Bite at base was pretty nice. I mainly used it as an attempt to counterteam Gardenia and used it on and off, but stopped around Galactic HQ where it was just not having good matchups with all the poison. Apparently I was one level off Quiver Dance though so I might bring it back for the postgame.
Dustox Lv 38
Light Screen/Toxic/Venoshock/Bug Buzz
Basically used it as with Beautifly but it did not really last either and had less useful opportunities.
Rapidash Lv 59 (shiny)
Flame Wheel/Smart Strike/Flamethrower/High Horsepower
Very cool and strong. I wanted a fire type and got this as my first Ponyta encounter so it also got some usage favoritism as my second highest mon. Flamethrower is actually pretty good since my offenses (150/127) are close together. I got an underground Ponyta later on to transfer High Horsepower onto.
Chatot Lv 43
Chatter/Roost/Hyper Voice/Taunt
I like Chatot so I picked up the ingame trade. Solid fighter for the midgame.
Togekiss Lv 51
Extrasensory/Air Slash/Dazzling Gleam/Yawn
Picked up from the Underground pretty early and pickupped a Shiny Stone at some point. Despite Hustle, it was good because of big stats and good moves.
Azumarill Lv 59
Double-Edge/Aqua Tail/Play Rough/Superpower
One of my favourite pokemon. Hits hard, bulky, and has the good STAB at base. Wide Lens patches accuracy up pretty well too. It also levels in the fast group too so it can catch up pretty nicely.
Cherrim Lv 47
Magical Leaf/Sunny Day/Weather Ball/Leech Seed
I grinded for a Weather Ball one in the underground before Wake. It was alright and did well against the waters even with one main move.
Lucario Lv 47
Aura Sphere/Bone Rush/Counter/Metal Claw
I didn't really use this frequently but it managed to get away with being underleveled at Snowpoint and caught up somewhat.
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Kazza Lv 26
My Flash user.
Combee Lv 27
My Sweet Scent user.
Ponyta Lv 1
I inherited High Horsepower and ended up breeding it down.
Dialga Lv 50
It trounced some stuff in the Sunyshore routes and electric gym but I decided to hold back for the sake of the game, though I probably could've replaced Jirachi.