- Compared to Fecundity - non-symmetrical; non-token only (biggest difference with Fecundity); have to pay 2 to get the draw, but it can be delayed. - But let's admit it, fecundity is kinda broken anyways.
- Compared to Lifecrafter's Bestiary - Worst case, it adds a cycle to every creature you have. Both have an initial cost. Bestiary adds a cost of 1 to every creature for the draw, Mysteries adds 2, but again - delayed as to whenever you want/can make the payment.
- Compared to Grim Haruspex - 1 life, vs. 2 mana per draw.
Overall, it's slightly worse of a card draw tool, and would fit only in the proper decks for it, but the ability to generate token artifacts (very rare effect), as well as make token creatures at a cheap cost in green (which is rarely seen on such a cheap permanent to put on the board), makes the combined package very appealing.
- Decks that are able to generate more than one death per creature, such as Karador, Ghost Chieftain can make good use of unbalancing the 1 draw per creature aspect.
- Decks that seek to add both draw and token production power, such as perhaps Rhys the Redeemed
- White/Green decks that seek draw and are running Cathars' Crusade could make good usage of it, as it helps multiple aspects of the deck plan.
- Decks that run Tireless Tracker can fuel up to get more clues and more tokens out of it.
- Decks that abuse artifacts like Clock of Omens or Krark Clan ironworks would love it.
- Decks that run Parallel Lives (or the new Amonkhet white version), can use this to double up on draws. -- and then quad up on the token production.
- Shattergang Brothers love this card, as it produces sacrificial artifacts to fuel his ability - and still get 1/1 creatures out of the deal to do more shenanigans!
Not an auto-jam-in into every single green deck, but a piece that can fit into several different puzzles, to be sure.
As another aside - this card singlehandedly won so many pre-release games for me...