Gen 8's DLC1 brought, alongside new moves, wider distribution of older ones to old Pokemon. One of the most benefitted ones was, without a single doubt, Mega Alakazam. Getting a blessed boosting move in Nasty Plot was enough to make it, on paper, much more viable than it was in the previous gens, taking advantage of its amazing coverage to tear apart most defensive cores after a single boost. Alongside it, Indeedee's Psychic Terrain support and Expanding Force meant it could have a powerful, boosted 120 (156 if counting Terrain) BP nuke most of the time.
At first glance, such a powerful offensive backbone immediately screamed "Hyper Offense" as its archetype. Having that in mind, participants all agreed that entry hazard support was, in fact, a must for the team. Deoxys-S won the poll over Celebi, Jirachi and Metagross. We chose the classic entry hazard lead Deoxys-Speed over the Dual Screens variant because hazard stacking softened up many defensive threats in theory.
The lack of physical presence on the team was immediately noted, and we didn't think once before putting in our next Pokemon: Victini. Psychic's small pool of physical attackers and Mega Gallade not being available meant splashing in the historic staple of Psychic teams was a no-brainer. A Choice Band set was the chosen one, enabling the team to hit hard on both sides. It also synergized well with Mega Alakazam by beating Psychic-type resists and special walls like Celesteela and Chansey.
Psychic's wide pool of viable offensive Pokemon kept us brainstorming for a while when deciding for the last two slots. Options like Hatterene to check Dragon-type teams better, Latias for Healing Wish support and Celebi for a bulky Water/Electric resistant pivot were all brought up, but we ended up with Latios as our Choice Scarfer and Jirachi as a secondary sweeper and Z-move user.
After finishing up the team and testing it for a while, we noticed it had some major flaws defensively that offensive pressure couldn't fill. Most faster Dark- and Electric- types seemingly ran through the team, as we had no response from them given Latios can only outspeed so much before dying and turning the team slow. Instead of opting for HO, Celebi was splashed alongside a SpDef + Healing Wish Jirachi set to create a more reliable variant of the team. Most people decided to use a wallbreaking Celebi set over a defensive one to have extra mileage against Water, Electric and Poison teams.