Ancalagon

i would play vines of vastwood over sheltering word

alesha, who smiles at death gets your master back and kills instantly if she is unblocked

loam lion?

you could cut out green and exchange the green cards with demigod of revenge and gurmag angler. could be worth trying

I would run goblin war strike and goblin bushwhacker

many llanowar elves + elvish mystics or other mana dorks could help
and I would cut out some less powerful wurms and the artifact/enchantment removal

when you want to cast the wums for free sneak attack is great. this with greater good is just mean

I think bloodbraid elf is banned in modern. Liliana of the veil could replace it

lord of the unreal and knight exemplar would work very well here

rancor for trample is always great

5 thalia's aren't legal, the rest is very solid. thalia, heretic cathar in the sideboard coul be good against aggresiv builds

+1
interesting, I would put out the liquimetal combo because it doesn`t fit in the deck. it is more important to find your blood sun. Additionally I think you need more to take value out of your mana: primeval titan is a classic in this kind of deck and spells like comet storm could finish very quick with enough mana. to use the ravnica double lands twice for extra value, voyaging satyr or kiora`s follower are great (tap for two). other ideas are life from the loam, azusa and crucible of worlds. to find your combo pieces you could use other blue card value cards like opt or anticipate

dark betrayl could help in the sideboard

+1, but I don't understant why you play 2 Path to Exile. If you instead play another 2 Abrupt Decay or 2 Maelstrom Pulse as removal, your landbase will be more simple, because you than need just black and green.
Another card you could try is Street Wraith.

first of all, i would cut out green, it's not the right colour for a non-creature player
maybe path to exile, condem, oblivion ring and/ or journey to nowhere
up to 4 supreme verdict are great if you don't loose something when you cast it (better than day of judgment)
better control counterspells: render silent, counterflux, negate, spell pierce, mana leak, dissipate, dissolve, dispel and crytic command
another good burn spell is magma yet

you can put out day of judgment, lava spike, planar cleansing, condecend, outwit, pacifism and the three green cards

an win con could be sphnx bone wand, but it's an artifact
luminarch ascension is strong to, but produces tokens
build around hedron alignment is a bit difficult, but could be fun

you have to add Fraying Sanity when hour of devestation is released.
(3b Enchantment - Aura, Curse
Enchant Player
At the beginning of each end step, the enchanted player puts the top X cards of his or her library into his or her graveyard, where X is the total number of cards put into that players graveyard this turn.)

surrak, the hunt caller

what about the both standart legal liliana's?

sorry, i wanted to suggest liliana, death's majesty, i think the otrher is a bit to expensive

lilliana, death's wielder?

ghoulcaller's chant for disentomb