Entei – Entei is needed to qualify for this challenge. Banded Entei paired with Sun gives this team an excellent wallbreaker with Sacred Fire spam, Extremespeed helps dampen the weakness to fast pokemon such as tapu koko, greninja and mega lopunny. The final two moveslots are used purely for coverage in iron head and stone edge
Mega Charizard Y - The other pokemon needed to qualify. Fire Blast hits like a truck, Solarbeam provides necessary coverage for water types, Focus Blast hits steels, rocks and dark types for super effective damage. Defog removes hazards that destroy fire.
Volcanion - Water immunity for those pesky swift swim teams, Bloom Doom allows for that ez 1 shot on a switchin to volcanion such as pelipper and slowbro. Steam Eruption + Fire Blast for dual stab and earth power for pesky Electric and Poison Types.
252+ SpA Volcanion Bloom Doom (190 BP) vs. 0 HP / 0 SpD Pelipper: 305-359 (116.8 - 137.5%) -- guaranteed OHKO
Torkoal – This slow turtle gives us that fun in the sun to halve Water damage and spin like a record and remove ugly rocks which hurt fire types. If it hasn't died yet it may be also able to place our own rocks.
Victini - The set is meant to set up/eliminate a threat like Bisharp and Excadrill, The shuca berry allows for this team to not be completely wiped by LO exca once in the sand.
252+ Atk Life Orb Excadrill Earthquake vs. 160 HP / 0 Def Shuca Berry Victini: 242-285 (63.5 - 74.8%) -- guaranteed 2HKO after Stealth Rock
Enough speed to outspeed jolly Lando-I is run (310) This also allows you to outspeed Meloetta, all +speed base 90s and below and neutral speed natured 105s.
V-Create and Bolt Strike combine to have decent coverage (I see you swampert) and allows this team to beat toxipex and other common victini switchins like Slowbro and Tyranitar.
Infernape - Scarf allows for easy revenge killing and provides a pivot which allows entry for the other members of the team.