Anyway, that's it. Not the longest thread, but it's good to update classic decks sometimes.
As always, if you want to read more about Expanded decks, you can check out my other threads, and/or join the Silent Lab Discord server! All links are in my linktree.
linktr.ee/lubyllule

(10/10)

This deck might not be the most innovative, but it's strong!
Another way to use Mega Lopunny ex would be to combine it with Garbodor: heavily disruptive Pokémon just benefit from a cost-efficient attacker to pair with. I might feature this deck in another thread at some point!

(9/10)

...while Karen combines very well with Vileplume's Item lock to rid Regidrago of its attackers.
Other possible techs include Alolan Muk, a more resilient but heavier alternative to Silent Lab, and Wally's Compassion, to heal Mega Lopunny ex even under Item lock.

(8/10)

With the core of the deck taken care of, it's even possible to fit a few more situational cards. Silent Lab adds more disruption to the deck, and V Guard Energy makes it harder to get KO'd by Regidrago. Pokémon Ranger is a mainstay to help against disruption such as Shadow Rider V's Shadow Mist,

Mega Lopunny ex's damage output is a bit lower than its alternatives, but we can increase it from 230 to 280 (key number to hit Regidrago VSTAR, Lugia VSTAR, Ceruledge ex...) with Choice Belt and Powerful Energy. Note that Guzma & Hala can grab both these cards, giving it more midgame utility.

This gives the deck more space for more draw Supporters, so we can run both Lillie's Determination for pure draw power and Marnie and N for disruption, and even a Call Bell which mostly acts as an additional out to turn 1 Guzma & Hala.

(5/10)

Now, what does Mega Lopunny bring to this deck? Space. Since it's a stage 1, it requires less spots than other possible attackers (Slaking ex, Dragapult ex, Hydreigon ex), and it doesn't need any specialized Energy. In fact, Gale Thrust benefits a lot from Jet Energy, so we can just max it out.

The core Supporter that makes this plan consistent is Guzma & Hala. It can grab Artazon, TM Evolution, and a Capture Energy (to search for a Pokémon) or Jet Energy (to get Bunnelby Active).
With Tag Call you can, essentially, play eight copies of it.

(3/10)

You might recognize the core from other Expanded decks: Bunnelby can attack twice in a turn, so it can use Evolution twice to evolve Pidgey and Oddish into Pidgeot ex and Vileplume on turn 1, setting up permanent Item lock and a search engine.

(2/10)

A fellow grass types appreciator!

Trouvez nous un moyen de guérir l'information du cancer que sont les milliardaires christiano-fascistes, et on arrêtera d'applaudir les œufs dans la gueule de ces pourritures.

They do see play, but not in this deck, which has no way to search for them

Hmm so if I play Standard at 2am I'm going to win the Expanded side event?

Salvaged my start into a 5-3 finish. Anyway, guess what I'm doing tomorrow!

Out by round 5 at 2-3. Very disappointing, I didn't have time to prepare for this format but I thought playing a similar Gholdengo list to last weekend would still get me in day 2. Oh well, I'll pick up the streak again in Toronto hopefully!