This is not just me, on EDHREC.com, the Arena is in 240,548 decks and Sign in Blood in 179,435, so tens of thousands less
A wider-ranging update to both the Trainer Card Maker and the website itself are both in the early stages of development
When mixed with a card like Deadly Dispute (which Ichor Wellspring is the main target to sacrifice for Deadly Dispute's effect), you get to draw multiple cards to get a nice refresh of your hand while ramping
Archangel of Thune and Celestine, the Living Saint are great because theyre solid cards all on their own, even without a bunch of lifegain
There's no blood, gore, or even knives showing, and the piece is all the more effective for it
Each other creature you control becomes a copy of that creature until end of turn, except it isn't legendary if the chosen creature is legendary