Lead Status (Butterfree) @ Lum Berry  
Ability: Compound Eyes  
EVs: 252 HP / 4 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Sleep Powder / Stun Spore
- Psychic  
- Hidden Power [Grass] / Giga Drain
- Morning Sun / Stun Spore
Optional Move(s):
- N/A
Optional Item(s):
- Leftovers
Optional Ability:
- N/A
Optional EV/IV(s):
- N/A
Overview: Butterfree cements itself as one of the most reliable status users in ADV ZU thanks to its access to Sleep Powder and Stun Spore alongside Compound Eyes. Paired with its above-average speed tier, this makes it a frightening lead, particularly versus slower leads like Snorunt, Growlithe, and Spoink, which almost always results in a sleeping Pokémon.
Lead Status: Sleep Powder almost never misses due to the accuracy boost from Compound Eyes. It puts switch-ins and leads to sleep, which makes them deadweight for most of the game. Stun Spore can also be run in addition to or in place of Sleep Powder in order to neuter faster threats such as Aipom, Pidgeotto, Taillow, and Elekid. Psychic is Butterfree's strongest move, and thanks to the absence of splashable Dark- and Steel-types, it is almost free to use. Hidden Power [Grass] allows Butterfree to OHKO Rhyhorn while also threatening Seaking and Staryu, but Giga Drain is an option to provide Butterfree a form of recovery that helps compliment Morning Sun's low PP, though it itself has low PP and is weaker. Morning Sun provides Butterfree with reliable recovery and allows it to keep itself healthy throughout the match. 
Other Options: Leftovers is an option to provide Butterfree with a form of passive recovery, particularly on sets lacking Morning Sun, but Lum Berry is great in the lead slot. 
Checks and Counters: Faster wallbreakers such as Pidgeotto, Aipom, and Taillow can all outspeed and OHKO Butterfree. Magnemite is able to completely wall Butterfree and use it to get behind a Substitute. Grass-types such as Sunflora, Bayleef, and Lileep are all able to wall Butterfree due to Butterfree's poor Special Attack when uninvested, despite 4x resisting their STAB. Lileep is worth noting due to its SpDef bulk and access to Rock Slide which has a 25% chance to OHKO Butterfree.