Monferno @ Choice Band 
/ Fist Plate / Firium Z* / Choice Scarf
Ability: Iron Fist
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature / Adamant Nature*
- Close Combat
- Flare Blitz
- U-turn / Swords Dance*
- Mach Punch
Monferno is one of the best offensive Pokemon in the metagame. It has a decent speed tier, great offensive typing and access to U-turn, which allows it to work as an incredible offensive pivot. While Monferno can threaten a large portion of the metagame, it struggles against bulky Pokemon that can take a hit and do something significant back, such as Mareanie or Grumpig. Monferno is also threatened by Pokemon that outspeed and KO Monferno without being significantly threatened by Mach Punch such as Mr.Mime, Oricorio-Baile and Silvally-Water.

Rotom-Frost @ Choice Scarf
/ Icium Z
Ability: Levitate
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Blizzard
- Volt Switch
- Thunderbolt
- Trick / Pain Split / Substitute / Defog
Rotom-Frost is the tier's best offensive pivot, with near perfect coverage with its Electric/Ice STAB, the ability to gain momentum through Volt Switch and access to utility in Trick, Pain Split, Substitute and Defog. Rotom-Frost notably breaks through some of the threats to Monferno mentioned above, such as Mareanie and Silvally-Water. Monferno and Rotom-Frost also make prediction more difficult for the opponent because both can hold Choice Scarf, making it sometimes difficult to predict which one is holding it.
---Teambuilding Weaknesses---
Pokemon who can survive a hit from from either Monferno or Rotom-Frost and threaten both pose a threat to the core, such as Sturdy Golem and Crustle, are issues for the core. Grumpig can also take on both members of the core as long as it avoids Trick, and Mareanie and Oricorio-Baile can punish the core's user if they get on the field against Monferno. Fast offensive Pokemon that outspeed the non-scarf member of the core while threatening both can cause serious trouble. Choice Scarf users which hit hard such as Chatot, Electivire, Mr.Mime, Oricorio-Baile and Simipour can also circumvent this core offensively due to their higher speed and ability to potentialy KO both members of the core.
(* = Use Together)