What makes the Shuriken so good is the massive power boost you could feasibly get off of it
Meanwhile, Psychic Corrosion is more expensive but also more powerful, since we get to mill for free each turn on our draw step and some of our card-draw spells draw us multiple cards to trigger Psychic Corrosion multiple times
That may sound extreme, but since the rules ensure priority has to pass all the way around the table (in turn order, starting with the player whose turn it is) before each spell resolves and between each step and phase of a turn, everyone is still able to play effects at the moments they need to
However, most constructed decks require specific cards in specific amounts, so unless you have all the cards required to build that specific deck or have enough wildcards to craft them, you probably wont be able to copy them straight away
This can help with resale records, trading references, and collection tracking.
[casthaven]Uthden Troll[/casthaven] The same as Horned Troll but in red