While I'm not quite sure exactly what deck wants this effect, this card is powerful enough that something will want to find some space for it. Now by powerful it's not a big flashy card that's going to usually win the game on its own, but letting all your creatures essentially kicker for a 1/1 flyer gives you a ton of grinding potential and the on board trick of being able to protect your more valuable creatures will make it quite awkward for your opponent.
Sure it's got a pretty hefty drawback, but one mana removal is something that should never be overlooked. In Modern plenty of decks are already willing to pay 4 life for a similar result with Dismember, though that has the advantage of being colorless. The jump from Ulcerate to say Bile Blight might not seem like much, it's just one more mana and how often do you need removal on Turn 1, but that one mana is much easier to work into a turn down the line. Plenty of games of magic are lost because one player gets locked into making one play a turn. Expect to see this out of the mono-black aggro decks, where the life loss is much less important, and mono-black devotion maybe want some number of them.
More potential cards for mono-Black, yay. This is another example of how much the difference between one mana can make. Read the Bones hasn't made much of a splash in Standard despite it being a very powerful Divination. The reason for this is that Read the Bones basically requires you to take a turn off from effecting the board or at least doing it so late in the game to matter less. Sign in Blood is much easier to work into the earlier turns of the game with a follow-up, and as an added bonus occasionally it will burn someone out as a Shock to the face.
I talked about this card in my last Hexproof article on the Designer Cards. The mono-green devotion decks on their nuts Nykthos, Shrine to Nyx draws are definitely in the market for Genesis Hyrda. They get to put a big creature into play and essentially tutor out another big threat from their deck. Casting this can flipping into one of your planeswalkers like Nissa, Worldwaker or Garruk, Caller of Beasts is a huge swing in your favor giving you a big creature, a planeswalker and whatever value you get from activating said planeswalker. That's quite the upset if your opponent is looking at a Hero's Downfall in hand. I also really like that this card plays well with Courser of Kruphix, letting you get some information on what you might want to cast Genesis Hyrda for.