TheBear

I would recommend just using Painful Truths over Read The Bones, the scry is nice but drawing the additional card is usually worth more.

Is this list one you found elsewhere or made yourself? I just find some of the numbers confusion and wondering why it's like that.
Just seems like there is a TON of Fetches that are not required, and could be more Stages/Depths, a fourth Maze, and I'm surprised there is no Crop Rotations or Entombs at all in this list.

Before the sideboard, for the mainboard, I'm confident you can cut down to 19 lands and cut the Murderous Cuts for 4x Gitaxian Probe, they are great on T2 to fuel Young Pyromancers.

For the Sideboard though, it really depends on what your meta is, I could think of a better choice of cards then. Otherwise here are just some good cards to include.

Izzet Staticaster
Dreadbore
Dispel
Forked Bolt
Leyline Of The Void
Fulminator Mage
Rending Volley
Painful Truths
Thoughtseize

I like the direction here, but some comments, why are you not playing Liliana of the Veil or Phyrexian Obliterator, they both seem insane in this style of deck. Could cut Lashwrithe, Whip Of Erebos, Command. And I think Demigod seems a bit lackluster in comparison to the other two cards. Then I think you need to get a bit more removal, feels a little light on it. Although if you have 4x Gatekeeper and Liliana, more or less you have 8x Edicts to fill the role.

I would recommend running a Roiling Thunder or two, I used to play Pauper and I remember that being one of the better choices for a Wrath effect, I would also prefer to use Ponder over Thought Scour in these style of decks.

Alesha is a legal commander because her abilities are W/B. When it comes to commanders it refers to the colors on the entirety of the card, for example. Memnarch is a "Blue" commander, because he has a blue activation cost. The same for Bosh, Iron Golem, where he's actually a "Red" commander for his Red cost in his activation.

I suppose if you look at it that way then yeah, could work.

Life From The Loam is your card advantage in all honesty, but the lack of Cycle lands doesn't give you an engine.
Mikokoro could fill the role, but that one I'm not sure about.

I can see cutting one Harvest, you have enough Dredge to find it eventually that the second copy isn't entirely required.

Luckily I played G/B Pox in legacy, so I know exactly what your deck is trying to do.
First, things I think you could cut.
1x Worm Harvest, if you have enough Dredge going, you'll find the single copy easy.
Syphon Life, I have tried it, honestly not the best card. I could see it maybe in the Sideboard against Burn decks, but that really is it.
Putrefy, Not the best removal, we'll come back to which ones are better in a moment.
Geth's Verdict, possibly keep 1-2, but the same goes with Putrefy, better choices.

Cards I think you do want are these ones.
Bloodghast, albeit expensive, it is much more efficient win-con, and with Life From The Loam, he will always recur and can easily be sac/discard fodder.
For the removal suite, Abrupt Decay would always be one of the best, but these are good replacements.
Go For The Throat, Kills everything but affinity creatures.
Smother, A toned down version of Decay, but does work.

Death Cloud could probably work in here also, you'll be better situated for the long grind games then other decks, so it would be more effective.

And the laughing is for.. ?

I've been tinkering with Mardu in Modern myself, and this is the big thing I find that pops up, the colors lack good creatures on 2 mana, besides Confidant, we got a shit ton in 3 and 4, not 2.

I would think you want atleast 3-4 more 2 drops, these are options I've found.
Tidehallow Skuller - More Disruption on a Body.
Pack Rat - Left unanswered still takes over the game.

Another interesting concept that has come to my attention during deck work, Butcher Of The Horde.
He works great with tokens from Souls and Brimaz, is out of Burn range and survives Slaughter Pact. Can also give large chunks of life against burn and an alternative way to get rid of Confidant if life does matter.

Instead Of Giant Growth, wouldn't it be better to run Become Immense?

It seems to be on the right track, but I do see some missing (And important) cards.
First, you really don't need 6 Storm cards, with the cards we add you'll only need the one, in particular Tendrals as it requires a storm of 10 for lethal, not 20 with Grape.

I can see cutting these cards:
Daze, could just be Force Of Will, or more Flusterstorms, as when you decide to go off, they should be high enough in storm count to stop anything.
Swords To Plowshares, Your deck in all honesty doesn't care for creatures unless they are hate creatures, but in that case mainboard you should be 100% focused on combo killing, not stopping threats.
Inquisition, Probably should just be Duress, for the same reasons as Swords above, it can take away a Force Of Will that Inquisition cannot.
Mind Twist, Your deck isn't much into disruption in all honesty.

These slots should be filled with the following cards,
Demonic Tutor and Vampiric Tutor, these will let you find your storm pieces,
Brainstorm, Ponder and Preordain, The Meat and Bones of card draw to help make your hand prepared to Storm off.

Last card would be Ad Nauseum, if this resolves and you are willing to pay the life, you will easily go off the next turn due to the amount of cards you will draw.

It looks pretty solid, although there are some things I'm not so sure of.

The Grisly Salvage seems really unrequired here, just by playing delver you will naturally fill your graveyard with spells, so using Salvage seems a bit of a win-more if you know what I mean.
I would personally only run 4 of the Delve creatures, in this case I would say a 4x Gurmag is best, Tasigur is great but this is a delver deck, you will run off 2-3 lands most of the time, so his ability is less impressive then a solid 5/5 that kills Rhinos. This is especially true since you are also running 2 Murderous Cuts, which in there own could be some other reactive spell, Remands, Spell Pierce, Etc.

That would leave you with ... 6 spots (If my math is correct), and since you said your rough match ups are Twin/Burn, these can be done.
A Fourth Abrupt Decay can be used, just a general good card, kills all creatures in Twin and Burn.

I would bring your Mana Leaks up to 4, it seems too good to only have 2.

For the burn match up I would recommend using Inquisition Of Kozileks, half the time it catches the same things as Thoughtseize without the loss of life, you could change the numbers a bit on how you want the split of Thoughtseize/Inquisition to however the meta is.

And last of all, you need the fourth Tarmogoyf, the card is too good to not include the 4x.

With these changes the sideboard would change a bit. I love the idea of Bitterblossom as some decks just can't beat it. Since we (If we go with what I said) You should have give or take 3 or 4 slots, just some general good cards can come in, Golgari Charm is great, a Maelstrom Pulse for big problems.

Just noticed now, you should put some Basics into your land base, Blood Moon seems like the kiss of death if it ever resolves on you.

That, but also a recurrable 2/2 with Mishra's Factory + Life From The Loam. And using Loam to fuel the Seismic Assault.

Sorry for the swarm there, Vault decided to post my message here three times for some demented reason.

Alright, so I think I understand this decks gameplan, just swarming your opponent with guys, then have Demon end it, so let's see what we can do.

First, with the manabase issues you said you had. I would cut all the pain lands for shocks/fetches in corresponding colors, if even more fixing is required, a 1-2 Mana Confluence isn't out of the question.

Now, the curve, which for this deck is important, here's the numbers.
1 cmc = 16 creatures, 20 with Lootings
2 cmc = 8
3 cmc = 6
4 cmc = 4

It feels very one sided to 1 drops, which in the end are not where most power is in Modern. We can fix this by upgrading the quality of our one drops as well as swap some things out.

Cards like Goblin Guide will give you much more power.
For higher curve cards, i.e 2cmc and 3cmc, these could be Dark Confidant for card draw, Goblin Bushwacker for an anthem effect on a body, which I think would be more efficient then using Rally The Peasants and even Bitterblossom for tokens. In the 3cmc, it's tough to find a good aggressive card, but Lingering Souls makes bodies and is always a good card, also works amazing with Butcher, and of all things, possibly even Goblin Rabblemaster, literally ALL removal in the format will kill him, but if left unchecked is a monster.

I would also recommend some form of interaction, even if it's a small amount. Like some number of Lightning Bolt and Path To Exile to get through blockers or deal the last points of damage.

Definetely looking solid, these are the only cards I don't like:
Grenzo, just doesn't feel like a deck you can really get a ton out of him with, since when you recur him, you won't actually get value. He's a better commander then a part of the 99.
Butcher Of The Horde, Just a fatty that is a sac outlet that can be killed but not recurred.
Ankle Shanker, His ability won't trigger when attacking with Alesha's ability, as it triggers when he attacks, not when he is already attacking.
Vish Kal, Same story as Butcher
Puppeteer, cool guy, but not 100% sure why he's here.

If you want to really abuse Deathcloud, it is with Planeswalkers, since they will not get killed by them. Liliana of the Veil is DEFINETELY the best, but not cheap at all.

The 4 mana Garruk in extended was a deck with Deathcloud, maybe try him out.
For the ramp spells, I don't think you need them. Your gameplan is to slow down the opponent and beat them down with attrition and disruption, so ramp isn't all that needed.