In fact you dont even need to use Polymerization
Based on my own experience with opening this set, here's the pull rates for Mega Evolution: Double Rares (ex): 21.8% or 1 in 4.6 packs Ultra Rares: 10.9% or 1 in 9.2 packs Illustration Rares: 10.9% or 1 in 9.2 packs Special Illustration Rares and Holo Rares: At least 1 in over 55 packs With that being said, here's some of the best cards I've pulled from Mega Evolution and where you can get them right now: Should you get Pokmon TCG: Mega Evolution
XY-Dragon Cannon X LIGHT Level 6 [ Machine / FusionEffect ] ATK 2200 DEF 1900 "X-Head Cannon" + "Y-Dragon Head" Must first be Special Summoned (from your Extra Deck) by banishing the above cards you control
Security meets accessibility with smooth-gliding, lockable glass doors that protect high-value items while keeping them fully visible to customers or guests
Lots of interesting data to look at
Log in RULINGS 2024-07-26 If the cost to cast a spell is increased, decreased, or changed because of additional or alternative costs, expend counts only the mana you actually spent