What are Pokmon's fundamentals
This four cost Amethyst card has a relatively straightforward ability, when it comes in to play, you draw a card
Once Drowsing Tyrannodon has attacked, it will remain an attacking creature even if you no longer control a creature with power 4 or greater
The text speaks for itself here - You can cast Dragon spells without paying their mana cost
It can stop treasure, yes, but it can also stop numerous combo pieces and value engines

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