Fell Stinger Qwilfish Sweep

Archeops uses Tailwind, then uses Endeavor after taking a hit. This allows Qwilfish to outspeed opponents and make a KO with Fell Stinger to increase its Attack 3 stages. Max Geyser can be used to set Rain, which again doubles its speed due to Swift Swim.

Scale Shot covers Dragon types and gives another Speed boost, which is helpful if Rain wears out. Waterfall can be used instead of Liquidation for Flinch RNG, or Throat Chop instead of Scale Shot for Psychic coverage. Speed EVs are set so it can oustspeed a Max Speed Calyrex during Rain/Tailwind.

Qwilfish @ Mystic Water
Ability: Swift Swim
EVs: 200 HP / 252 Atk / 56 Spe
Adamant Nature
Fell Stinger
Scale Shot/Throat Chop
Poison Jab
Waterfall/Liquidation

Archeops @ Focus Sash
Ability: Defeatist
EVs: 252 Spe
Jolly Nature
IVs: 0 HP / 0 Def / 0 SpD
Tailwind
Endeavor
Taunt
Stealth Rock

Music: Symphony No. 94 in G major 'Surprise' by Franz Joseph Haydn