Like most Pokmon cards, the value of Charizard-EX depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (XY Black Star Promos)
While his origins in the anime are relatively traditional for a shonen antihero, his first appearance in the manga is (perhaps predictably at this point) absolutely bonkers
That said, for just a dollar and a mana, you get an artifact that basically pushes your mana two turns ahead for the price of one
a dark and bold signature of Adolf Hitler hand signed (autographed) in black fountain pen ink
The second most valuable card in this set is the all-gold Mega Hyper Rare Mega Charizard X ex, which goes for around $325
This is the card you want, except for