I was able to summon Sisters of Avalon turn 1 to discard a Great Old One (or any powerful minion) then followed up with Boneyard on turn 2 to resurrect the Great Old One
There are other ways to acquire booster packs than your daily allowance, to give you even better odds of completing your Dex
Battle Task: Knock Out your opponents Active Pokemon 1 time with an attack from a Darkness-type Pokemon (rewards 4 Event Hourglass) Put 3 Basic Pokmon into play (rewards 4 Event Hourglass) Chance Rewards: 1 Promo Pack B Series Vol 3 (51% chance), 1 Shop Ticket (38.7%), and 25 Shinedust (100%)
If you want to build around this card, Toph, Earthbending Master delivers
As long as Melira is on the field with Phyrexian Vatmother, you wont receive any poison counters on your upkeep if you need more time to draw into your win condition
Regretful Pikachu (top left) This Pikachu gives off strong vibes of regret