Selling in volume brings marketplace fees, shipping, time, and often a discount
Conversely, during deckbuilding, a Pokmon ex and its base version are treated as separate cards for the two-cards-per-deck limit, so if you wanted to, there's nothing stopping you from running two Charizard ex and two non-ex Charizard
But being able to shut down your opponent just by existing is why this card takes the number one spot on this list.
Roll X six-sided dice
Note that as a combo-ish deck, you can be interupted quite easily on certain step, but the gameplan (always stick to the gameplan !) is : If you have parallel exceed : splash a mathmech to the field, preferably addition, soustraction using opponent cards, or sigma if needed
Summoning sickness only stops creatures from attacking and activating abilities that use the tap symbol as a cost