Its hard to say that Hylda will see Standard play because these cards usually underperform, and it looks interesting in EDH at least
Now, everyone knows Zirda can do busted things with Basalt Monolith or Grim Monolith to generate infinite colorless mana, and thats certainly wild the first time you do it, but lets face it, easy-mode Magic gets boring fast
The triggered ability does make it at least somewhat more interesting and does deal more damage than red cards usually do
For One Mana highlights one mana cards you could be playing but arent, in an attempt to make you diversify your one mana plays over grabbing the easy auto-includes you keep seeing in every game
There are also ways in Golgari to buff creatures, so if you increase Jenova's power, you can both buff your other creatures more, and draw even more cards when they die
Fuming Effigy Unlike other cards that may trigger only once when creatures leave your graveyard, you can use Fuming Effigy as a finisher to start pinging the whole table at once