D-Tier??? RU Kidding me? (joke joke...).
This prehistoric flying Dinosaur may be ancient but definitely deserves a little more recognition and not go extinct. Check it. Base
130 Speed. In the OU Metagame, that shit is just godly. Being able to outspeed practically anyone (which includes base 129 base speed Pokemon and below along with base 70 Scarfers...which is stupid 'cause those don't really fly around a lot haha), Aerodactyl introduces itself with quite a flashy showcase of speed. Next up, is his offensive stats. Base 105 Attack is above average and quite solid. It pales a bit when put up against the OU Titans such as Lucario, Terrakion, Conkeldurr, Mamoswine, Dragonite, Hydreigon and so forth. However it's good enough that it is quite useable. (I mean it's more offensive than stuff like SD Gliscor at least haha). Aerodactyl is almost always running Sash with Rocks and Taunt. This really allows Aerodactyl to stop entry hazards from coming up on your side while putting your on Rocks up. He works well against stuff like Sash Terrakion. EQ is a solid 2HKO and thanks to Sash+Higher base speed, Terrakion will either have to run and allow an opportunity for Aero to set up Rocks OR Terrakion can be KO'd and you can battle worry-free of those troublesome rocks. Aerodactyl has Hone Claws which isn't terrible. It has its uses. Stone Edge misses became a laughing matter as he boosts. One time is enough to bring Stone Edge to a comfortable level of usage and reliability. With Rocks up and a +1, Aerodactyl can do some work to a worn down team. Keep in mind, Aerodactyl is better off utilizing a Focus Sash and it better off in the Sand (it really helps).
+1 252 Atk Aerodactyl Earthquake vs. 4 HP / 0 Def Terrakion: 308-364 (95.06 - 112.34%) -- guaranteed OHKO after Stealth Rock
+1 252 Atk Aerodactyl Earthquake vs. 156 HP / 0 Def Tyranitar: 260-306 (68.42 - 80.52%) -- guaranteed 2HKO after Stealth Rock
+1 252 Atk Aerodactyl Stone Edge vs. 4 HP / 0 Def Latios: 255-300 (84.43 - 99.33%) -- 75% chance to OHKO after Stealth Rock
+1 252 Atk Aerodactyl Stone Edge vs. 184 HP / 4 Def Rotom-W: 198-234 (68.98 - 81.53%) -- guaranteed 2HKO after Stealth Rock and weather
Just some random calcs, but you can see that Aerodactyl is not terribly outclassed as an offensive late game cleaner. His plethora of Priority weaknesses is obvious but again, they should have received prior damage and a Sash should be held by Aero to ensure Aero can go and take them out.
Aerodactyl is a Pokemon with a hell of a lot of flaws. But, he has his perks. D-Tier sounds a little too harsh.
"Reserved for Pokemon who can be effective given the right support, but either have crippling flaws that prevent them from consistently executing their strategy or are completely eclipsed by a Pokemon in the above ranks." C-Tier really sounds applicable. With Support as listed, Aerodactyl can work surprisingly well for a "poor" Pokemon in this Meta. He does have crippling flaws though and this does hold him back. But Aero is definitely "worth the time" and can fulfil more than just a "tiny niche".
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