Bears are Dinosaurs too, right? (Standard)

Ramping Dinosaurs has existed since WotC announced Ixalan. It is not a new concept. This is a slightly different take on it.

The decks engine:

a) Goreclaw, Terror of Qal Sisma
a main goal of the deck is to play Goreclaw by turn three. Afterwards you can drop cheap bombs.
Goreclaw is easily removed, but that is less removal for your opponents to play on the gigantic Dino's that follow.

b) Sarkhan's Unsealing
*this is the grand-daddy of all bombs if left unchecked. A minimum of 4 damage for every creature you play from this point on. Playing a Carnage Tyrant or Ghalta is just silly.

The Ramp:
*We are playing absolute bombs, so we need some serious ramp. I chose to go the creatureless ramp route as I want more consistency. It is just harder to defend against this ramp than it is to shock a mana dork.

a) Thunderherd Migration
should be a non-issue to cast this turn 2 every time you start the game with it.
this deck wants to 4 mana on turn three whenever possible.

b) Grow from the Ashes
this is a solid backup ramp plan if we do not draw Thunderherd Migration.
there is a fair amount of removal out there for enchantments so I would be worried about playing Gift of Paradise. The 2 for 1 of Assassin's Trophy makes it an impossible play right now.

The 4 power + creatures:

a) Ripjaw Raptor
while it is a decent threat to attack with, it is a phenomenal blocker. This just gives RDW trouble since it can block almost anything they play and is hard enough for them to remove as is, but you will draw cards off their removal attempts as well.
we may also play a few cards that trigger enrage.

b) Territorial Allosauras
*cost reduction really allows you to go for the kicker here. At worst you play a 5/5, maybe as soon as turn three.

c) Regisaur Alpha
*the bodies are so much power to deal with when ramped into, but the main reason to play it is to give everything else haste.

d) Trapjaw Tyrant
*has a lot of the same upside as Ripjaw Raptor. Sure, they can get their creatures back over time with their own removal, but it stalled the game long enough for us to build up a crazy board.

e) Carnage Tyrant
*the true bomb in every way.

f) Etali, Primal Storm
the body is right on curve, but that trigger can be explosive.
Etali boarders on being win-more, but this is a dino ramp deck so everything about it is go big and win or lose miserably.

g) Ghalta, Primal Hunger
*not as good here as in mono green stompy asyou will not drop a creature until at least turn 3.

h) Gishath, Sun's Avatar
*this is the definition of win-more, but this deck cries for at least one normally unreachable bomb.

Utility Cards:

a) Deafening Clarion
it takes us a while to get going and this buys us time by holding back any aggro decks we may run into. Also, a great play against the explore creatures running all over the meta right now.
giving a couple of the decks dino's lifelink can swing you back into a game pretty fast as well.
*triggers enrage late in games while not killing our creatures. This is a pretty big value outcome... kill opponents smaller guys, draw a card and/or exile a bigger threat, give your dinosaurs lifelink before they attack.

b) Prey Upon
*not the ideal form of removal but we are packing huge creatures and enrage triggers.

c) Response // Resurgence
Response is solid removal in this deck since we are slow going so it will be online to kill attacking creatures, and is big enough to kill any creature that comes down before our dino's.
Resurgence is a total chance at a blowout. Probably any two dinosaurs can finish a game with two chances at swinging. Etali and Gishath are totally broken here.

What to do with the 4 remaining slots?

*At this stage I feel the deck has enough going on in the midgame. After the deck ramps I am satisfied with the options that come after.

*What concerns me the most about the deck is that if my opening hand does not have Thunderherd Migration then I am taking the first two turns of the game off. Standard is not the fastest of formats, but I'm willing to bet that taking turns 1 and 2 off has a very low win percentage.

a) Pillar of Origins
I was looking for another option for turn 2 and was getting nowhere. I was looking for a card that would either greatly slow my opponent down or in some way make sure I bought time to set up. I considered all kinds of whacky solutions: from gaining life, playing high toughness creature that could block, consistent removal, and mana dorks. Mana dorks work against the deck, as I stated before, especially with Defeaning Clarion as a major plan early on.
Pillar of Origins is not perfect as it misses Goreclaw and Unsealing (which is what we really want to be doing on turn 3. What it does do is give us a way to ramp into the Dinosaurs that come after. It is a viable plan B.