Technically you can have as many as you want (assuming you can shuffle it in your hands), but thats a talk for another time
currently, you can spend $23 to get 120 gold and a suite of Gardevoir-themed customization items, like playmats and card sleeves
On the surface, milling ten cards in a turn for each of your opponents might not seem like much, but add in a few other unblockable creatures and maybe a few effects that let you steal your opponents high powered creatures to attack with, and suddenly everyone is milling tons of cards each turn
Every single artifact, be it a Treasure token or a Celestus, could be used to ping your opponent
The three categories are: Name: This allows you to search for cards that have whichever specific word you search for in their name
Waxen Shapethief Flash and cycling on just about any card add good options