For example, Curiosity is a simple, incredibly cheap, and aggressive draw option, but pales in comparison here to Combat Research, which functions similarly while also providing protection and a power increase for Arna and the decks other Legendary Creatures
Essentially, it lets you destroy creatures or artifacts, and then their owner gets to play the same number of random artifacts or creatures from their library
We can also do incredibly fun stuff like proliferate divinity counters on Myojin of Seeing Winds to draw cards equal to the number of permanents we control, multiple times
Crucially, many sit on the Reserved List a publisher's vow never to reprint them
The Protection offered up by Shelter and co
This card is just good in a deck where counters matter without any effort