Pokémon Yanmega

[Rawbi]

Bug/Flying
Base Stats: 86 HP / 76 Atk / 86 Def / 116 SpA / 56 SpD / 95 Spe
Abilities: Speed Boost / Tinted Lens / Frisk (H)
Notable Moves:
- Air Slash
- Bug Buzz
- Ancient Power
- U-turn
- Protect
- Giga Drain
- Shadow Ball
- Psychic
- Tera Blast

Pros:
- Tinted Lens attacks off base 116 SpAtk, especially when boosted by Choice Specs, makes Yanmega a powerful wallbreaker
- Speed Boost allows it to outspeed the majority of the meta after a +1, providing a cleaner role instead
- Has just enough move coverage to hit mons that would otherwise wall
- Terastalizing allows Yanmega to ditch its awful defensive typing and SR weakness while luring checks

Cons:
- Massive Stealth Rock weakness -- though HDB can alleviate this, Yanmega really wants other items like Specs or LO
- Base 95 Spe is a middling speed tier
- Somewhat frail, with few useful resistances

Tera Potential:
Tera Rock turns Yanmega's Fire and Flying weaknesses into resists, while Tera Ground does the same for the Rock and Electric weaknesses. Both types combined with Tera Blast can smash through checks and counters like Moltres and Garganacl. Tera Bug is a further boost to Yanmega's Bug Buzz.

Potential Sets:

Specs Wallbreaker
Yanmega @ Choice Specs
Ability: Tinted Lens
Tera Type: Ground / Rock / Bug
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Bug Buzz
- Air Slash
- U-turn
- Tera Blast / Giga Drain / Shadow Ball

The tried and true Tinted Lens abuse set. Bug Buzz is Yanmega's strongest move, leaving dents even in mons that resist. Air Slash provides secondary STAB and handles Fighting types that want to absorb BB. U-Turn gets Yanmega out of bad matchups. The last move slot can be tweaked to cover threats that would otherwise handle Yanmega's main two moves. Ground Tera Blast deletes Kingambit, Gholdengo, and Galarian Slowking, among others. Rock Tera Blast removes Flying types, notably OHKOing defensive Zapdos. If you don't want to dedicate your Tera to Yanmega, then moves like Giga Drain or Shadow Ball can lure checks, though they're nowhere as strong.

Late-game Cleaner
Yanmega @ Life Orb / Heavy Duty Boots
Tera Type: Bug / Ghost
Ability: Speed Boost
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Protect
- Bug Buzz
- Air Slash
- Giga Drain / Shadow Ball

This set aims to use Speed Boost to outrun and outgun weakened teams. Protect allows a free +1 Speed, putting Timid Yanmega at a brisk 475. Life Orb boosted Bug Buzzes and Air Slashes are hopefully enough to finish off stragglers. If you have not spent your Tera on something else, Tera Bug helps Yanmega net remaining KOs, while Tera Ghost avoids common priority moves.

Though Yanmega will most likely not be an OU staple, I believe the strength of its Choice Specs set may make it a niche pick. Teralization gives Yanmega more flexibility in luring its checks -- something it could do in the past, but not to this degree.

 

[RoyalDispenser]

The day this thing gets nasty plot, calm mind, or even quiver dance is the day it'll become legitimately good.

Its so sad how much potential it has if its only boosting move wasn't just.... sword's dance on a special attacker... and its speed was just a tiny bit higher than 95 so tinted lens could shine better.

In a desperate attempt to make it work, here's a funny set I cooked with back in gen 6 that seems to still work now;

Yanmega @ Weakness Policy
Ability: Speed Boost
Tera Type: Fire
IVs: 0 Atk
- Endure
- Bug Buzz
- Air Slash
- Tera Blast

Running tera fire cause that just makes sense, but the gimmick is you send it out, take advantage of the fact bug/flying has a ton of weaknesses, press endure, and get a +2 SpA boost, plus a speed boost for the turn. Since Hail is gone and its Snow now, you have a bit more safety being 1 HP all the time and there's plenty of ice types to proc your weakness policy, but obviously priority moves will ruin your day. It is a bit gimmicky, but if you're seriously planning to use yanmega in OU you're probably just doing it for fun, and gimmick sets are fun.

You could run yanmega behind veil now, since again snow doesn't hurt you, and thus proc weakness policy without wasting an endure turn, but either way this mon isn't good enough for the tier.