Edit: Sorry! Didn't realize Landorus-T had already been done, so I decided to do Heatran instead.
View attachment 129128
Name: Walking Furnace (Heatran)
Nerfed Stats: 91/80/76/115/76/69 (-10 Atk, -30 Def, -15 SpA, -30 Def, -8 Spe,
-93 Total)
Removed Moves: Solar Beam, Taunt, Stealth Rock, Stone Edge
Ability: Flash Fire
Typing:
New Moves (If Any): N/A
Justification: Heatran is one of the best Pokémon in OU at the moment, due to its combination of bulk, incredible typing, power, and amazing ability. When making this nerf, I wanted to preserve Heatran's defining characteristic (A Steel-type that does well against Fire-types and is more specially based. Cutting into Heatran's bulk turns it from a great switch-in to many of OU's top threats into a Pokémon that has difficulty getting in. It's bulk is now lower than most of OU; some more offensive Pokémon even have more bulk than Heatran, such as Landorus-T, Keldeo, and Serperior. While Heatran is not frail, the amount of Pokémon it can defensively check and counter has dropped. Removing Stealth Rock and Taunt hurt Heatran's ability to play as a hazard setter and a stallbreaker. Removing Solar Beam and Stone Edge dent its coverage and makes it harder for Heatran to answer Water- and Flying-types. This is coupled with a 15 point drop in Special Attack makes it overall less powerful than most of OU's bulky attackers. Lastly, a just missing the base 70 Speed tier causes Heatran to be outsped by Mega Scizor, Tapu Bulu , and Mega Swampert in OU, as well as Decidueye, Hitmontop, and Garbodor in NU. While this is not a defining Speed tier in either tier, it does lessen Heatran's ability to hurt pokemon it would otherwise counter.
Competitive Insight: As previously mentioned, Heatran is meant to be a powerful special attacker that uses its fantastic typing and ability to switch into many threats. Magma Storm is still a fantastic move that heavily damages and traps threats, forcing opponents to play a deadly guessing game with Heatran. Heatran can act as a bulky pivot to pressure many teams, seeing as very few Pokémon have a way to deal with its reliable STAB and defensive typing. Earth Power allows Heatran to threaten a 2HKO or 3HKO on most NU Fire-types, such as Incineroar, Delphox, and Houndoom. This is even more potent with a Life Orb or Choice Specs set. It also has surprisingly good bulk for NU, allowing it to take down Sneasel and Diance. Finally, a Choice Scarf set outspeeds base 110s such as Dodrio. However, Heatran is destroyed by Slower, who is never 3HKOd by Heatran and can 2HKO with Scald. This is made even worse by Slowbro's fantastic ability in Regenerator and access to Slack Off, allowing it to remain a Heatran counter for the entirety of the match. Slowbro's high usage and viability only add to Heatran's problems. Ground-types also threaten to OHKO Heatran with their STAB, and are common in NU. It is important to note however, that Steelix, the best NU Ground-type, has a secondary Steel typing. Due to this, I suspect Heatran to be in mid-high A tier in NU due to its ability to pressure many top tiers such as Sneasel, Incineroar, and Vanilluxe, despite its problems with Slowbro.