Judging the value of a Pokémon depends a lot on what job you are asking it to do in Pokémon Go. A Pokémon that is an excellent gym attacker might make for a terrible defender. Is that Pokémon better than a Pokémon who can both attack and defend, but isn't great at either?
This is why "best of" lists all have their unique methodologies to try to answer the question of which Pokémon are superior to all the rest. The Pokémon that continually rise to the top of any list, no matter how it's been determined, are the best Pokémon of 2016.
Pokémon Go best Pokémon: How to determine the top 20 fighters
Niantic patched Pokémon Go on Nov. 21 with a balance update that adjusted the stats for every Pokémon in the game except Lapras. This update necessitated rethinking every top 10 and top 20 list the experts had presented prior to the change.
All the data by which we're going to figure out the top 20 Pokémon in Pokémon Go is therefore relatively fresh. We are drawing from three sources here: GamePress, the Total Damage Output-based analysis from Redditor Qmike (a member of The Silph Road community), and the matchup-based simulations provided by Silph Road member QuantumOverlord.
We looked at how often a member of a species of Pokémon appeared in top 20 rankings for attacking and defending, and where they appeared on the list. We also considered how many times an individual member of a species showed up in the top 30 for best attackers and defenders.
Finally, we made an assessment as to what a particular species of Pokémon was best suited to do. For instance, a Pokémon that is excellent at attack may be so good as to balance out their complete lack of value as a defender.
Mew, Mewtwo and the legendary birds were also removed from any data sets we used, as we wanted this list to contain only Pokémon you may actually catch at this time.
Drowzee seems to be relatively common in Pokémon Go, making Hypno one of your best defenders in the early game. It can also make for a potential speed bump as a gym defender in endgame play.
Gengar earned a spot on this list for its attack skills. Don't bother fielding Gengar as a defender unless you have to, but with the right moves Gengar can give even proper endgame Pokémon a hard time during a gym battle.
Considering how iconic Charizard is in the Pokémon franchise one would think it would amount to more in Pokémon Go. But while Charizard might make for a good attacker compared to most Pokémon on the top 20 list, it can't hold a candle to the true endgame fighters like Snorlax, Dragonite, Lapras and Vaporeon.
To be honest, Vileplume is a third-tier attacker. Not a competitive endgame Pokémon, but maybe a good choice for attack squads in the early game.
Alakazam only started appearing on multiple top 20 lists after the balance update, so it's a relatively new consideration as a serious endgame Pokémon contender.
Alakazam can be an excellent attacker, considered Tier 1 and top 10 on several lists. That's about all Alakazam is good for, however. Don't waste it on defense.
Role: Multi-purpose, slightly better defender
Muk places top 20 on both attacker and defender lists but is a third-rate attacker at best compared to endgame Pokémon.
Cloyster has little if any value as an attacker. It is a useful bulwark as a gym defender against lower-level attackers, but unless you are really hard up you may never field Cloyster as part of an attack squad.
Poliwrath is a top 10 defender on some lists, but that's about all it's good for from an endgame perspective. Poliwrath can't hold a candle on offense against the big boys but he can frustrate lower-level Pokémon during a gym battle.
Role: Multi-purpose, not particularly good at attack or defense
Omastar is not what you might normally think of as an endgame fighter, but it shows up on both top 20 attacker and defender lists. It's not very good at any one thing, however, so Omastar is probably best only against lower-tier Pokémon.
Role: Extremely good defender.
There's not much more to say about Chansey other than to cite its basic role because defense is all Chansey does. It can be a brick wall following the balance update. Put Chansey in control of your gyms wherever possible.
Role: Attacker. Little value as a defender.
Jolteon, an evolution of Eevee that players can control by using the Eevee name trick, can do a fair amount of damage given the optimal moveset. However, Jolteon is fairly useless as a defender.
The best use for Jolteon in your attack squad might be to probe enemy defense. It's also a good lead Pokémon to swap out for other attackers as the situation requires.
It's easy to dismiss Slowbro as a goofy-looking Pokémon, but with the optimal moveset he can be a solid gym defender right up there with Snorlax and Lapras.
Role: Best at attacking
Venasaur isn't a very sexy Pokémon. You won't read about it nearly as much as any of the top 5 Pokémon but Venasaur can still pack a hell of a punch.
If you're going up against a Venasaur during a gym battle, considering putting it up against your very best defender.
Perhaps it's only fair that Gyarados doesn't break the top five list in either attack or defense. Anyone who doesn't live near water is likely going to have a difficult time gathering 400 Magikarp candies to evolve a Gyarados. So it wouldn't be right for it to be too powerful an attacker.
Attacking is still what Gyarados is best for. You may see them defending gyms in the game world but that's not its optimal role. If you can save one for your attack squad, do so.
Role: Multi-purpose, better on attack
Rhydon's rise into the top 10 was paved by the balance update. Pokémon Go players following the update noticed that Rhydon had become a really good attacker. In fact, it may be able to compete with Snorlax, Dragonite and even sometimes Vaporeon on that score if it has the right moveset.
Rhydon can also serve as a defender and will give non-endgame Pokémon a relatively hard time if they attack. You will probably get more out of Rhydon if you keep him on offense, though.
Role: Multi-purpose, better on defense.
Exeggutor is another endgame Pokémon that can fill multiple roles, although its total damage output might be lower than any other endgame Pokémon on our list.
On defense, however, Exeggutor has the potential to stand alongside Snorlax and Lapras.
Role: Multi-purpose but superior on attack.
Vaporeon has been an endgame Pokémon since the very beginning. It also exploded in popularity after the Eevee name trick was discovered, allowing anyone who wanted a Vaporeon to evolve one.
That left a lot of room for experimentation with different Vaporeon builds, and so the data on this Pokémon's battle prowess is substantial. Vaporeon was nerfed slightly by the balance update but it's still a powerhouse you can always expect to contend with.
Role: Multi-purpose, excellent defender
Of the top three Pokémon species in Pokémon Go, Lapras is the best defender with Snorlax close behind.
Lapras is no slouch on offense, either. It's a top five attacker just behind Snorlax, but if you can save Lapras to defend a gym, you'll get the most out of this Pokémon.
Role: Multi-purpose, better on attack
With the right moveset, Dragonite is a devastating gym attacker — even better than Snorlax or Lapras. If you want a Pokémon that can rip through the early defenses of an enemy gym to expose the heavy hitters at the top, Dragonite is the Pokémon you want to lead with.
Dragonite can also play defense if you need it to. Like any endgame Pokémon in Pokémon Go, Dragonite is a multi-purpose fighter. Try to keep Dragonite available for offense, however, rather than slotting it into a gym defender position.
Role: Multi-purpose, slightly better on defense
Snorlax is the only Pokémon on our list who is considered Tier 1 in both GamePress attacker and defender rankings. At least five different possible Snorlax movesets appear in the top 30 Total Damage Output lists.
So it doesn't matter which variety of Snorlax you get. When you find yourself a Snorlax, you just caught the best Pokémon in Pokémon Go.
More Pokémon Go news, tips and tricks
If you're so into Pokémon Go that you would love to argue with us about our picks, you may also want to check out Mic's other Pokémon Go content. Here are guides on how to catch Gen 2 baby Pokémon, the 98 Gen 2 Pokémon that have yet to be added to the game, how to catch Pikachu and his adorable new Christmas hat, post-update Chansey and Rhydon, everything you need to know about finding the long-awaited Pokémon Ditto, creating new PokéStops, how to maximize your chances of catching Pokémon and fresh information about how PokéStops distribute Pokémon eggs.