Any enters or dies ability on one of your creatures, any activated ability from any source: its all fair game
Rhystic Study In theory, its possible that [c]Rhystic Study[/c] never draws you a card in a game of Magic, but then your opponents are greatly limiting their plays
As for the card itself, Eldrazi Conscription is pretty much solely played in Commander
The front half is a very solid removal spell, while the back half can end the game on the spot if it goes long enough
Its interesting to see Blue shift into token generation rather than fall into hard countermagic and clunky win conditions
Cards like Isabella Madrigal, Caring Cultivator and Ming Lee, Giant Red Panda both interact with damage counters and healing, but The Madrigal Family only really offers high willpower and ink ramp, which isn't enough to offset the volume of other, more useful cards in this set