Replaced Tasigur, the Golden Fang with Rakshasa Deathdealer because Yikes! Tasiugr is not worth 10$. I might upgrade if he goes down in price

Will increase CMC of deck, BUT Undergrowth Scavenger instead of Rakshasa Deathdealer?

@plusmental well, Tasigur, the Golden Fang would be ideal, but I chose Rakshasa Deathdealer because i needed to not have a totally dead early game. I also feel that Undergrowth Scavenger's inability to grow is less than ideal, but thanks for the suggestion.

Temporal Trespass is fairly useless in this deck, wheras a Treasure Cruise would be insane.

Also, Dead Drop in sideboard for hexproof/indestrutible

Temporal Trespass has consistently won games for me. I don't need a hand full of cards, because my graveyard shenanigans with Whip of Erebos and other cards gives me card advantage, so Treasure Cruise is unneeded. Dead Drop is an idea, but the only thing that has hexproof and indestructible is Fleecemane Lion, so that's one card in standard that can be removed preemptively. Silence the Believers and Archfiend of Depravity can get rid of indestructibles, while Fade into Antiquity can remove gods, and Hornet Queen can stop hexproofs, so I like my current setup better, but thanks for the comments.

I would cut two Nighthowler for something else

Dead Drop kills Gods.

Hornet Queen and no Elvish Mystic? If you aren't lucky enough to discard the bees, then you will be stuck before you can play one from your hand.

I would take out one Nyx Weaver before you deck yourself (I've seen it happen with only one), and maybe one of the Sidisi, Brood Tyrant, as well as one or two Nighthowler. Grave Strength is bad even in this build.

Hero's Downfall would be nice in there as well. Liliana Vess is also brilliant in this kind of deck. You slow your opponent down, you get the chance to go find a new Whip of Erebos if yours gets removed, and if you go ultimate with her, just think of all the creatures you have been milling and didn't exile so far, that alone would win you the game, but getting your opponent's graveyard as well, is just priceless. (I know the Downfall and Liliana are a bit spendy, but they would be major improvements)

Undergrowth Scavenger doesn't grow after you play it, but it also doesn't get smaller, which let's you use your Whip at your will. It's a good card, but I still like the Nighthowler more, since you can bestow with it. Nemesis of Mortals might also be interesting and even though I hadn't give any thought to this before Rakshasa Vizier and Marang River Prowler might do some interesting things in here!