Klasper

Forgot the most important thing

Rings of Brighthearth is another real possibility to go with Magosi

Exciting to see a new approach on Magosi. It's a pretty demanding combo you got, but interesting none the less.

I'd probably add some contagion clasps for earlier proliferation.

Also I'd swap out the birds of paradise for Joraga Treespeaker (or other stuff that tabs for at least 2 mana), to give you mana ramp together with Aura of Dominion.

You could also consider cards that can untap your lands (might make you able to combo magosi, without giving your opponent a double turn). This could be Sword of Feast and Famine, Bear Umbra or Copperhorn Scout (after animation of the lands)

I'd probably trim the spells a bit, to make room for walls

-2 Cabal Ritual (threshold condition will be hard for you to get early on)
-4 Ponder
-2 Rampant Growth

Then I would add

+4 Overgrown Battlement
+4 Fog Banks (or Guard Gomazoa for a newer versions)

Shield Sphere are nice too for early aggro

you are dead well before you get to use Karn, or your opponent will have creatures to attack Karn with so you won't be able to use his ultimate.

You should get some walls at least, like overgrown battlement. Alternatively some control.

Kargan Dragonlord is indeed a beast, especially because of the versatility of leveling, good call.

Seems a bit too top heavy for my liking.

I'd add some 1 or 2-drops. Like Goblin Arsonist.

To make room I'd cut down on the number of planeswalkers, so you are left with 2 of each. On top of that I'd also take out a titan and a hero of oxid ridge, and board in two red sun's zenith.

So something Like:
-2 Chandra
-2 Koth
-1 Hero of Oxid Ridge
-1 Inferno Titan
+4 Goblin Arsonist
+2 Red Sun's Zenith

Always liked the kuldotha aggro.

With the perfect hand (as I see it) with 2 mox opal, great furnace, 2 memnites, kuldotha rebirth and bushwhacker this deck could pump out 14 damage turn 1.

T1: Great Furnace, 2 Memnites, Mox Opal (tap + sac) -> kuldotha rebirth -> Mox Opal -> Kicked bushwacker -> Attack with 7x 2/1 haste creatures

As you say, seems hard to stand against heavy aggro with this, other than that it looks pretty mean.

Maybe get some flame slash side-boarded against creature-aggro

Sorry to say, but Magosi, the Waterveil SUCKS!

You can't proliferate it, to take more turns, cause you need to return it to your hand when you tap it for turns (all counters are therefore lost).

I also remain sceptical as to you having 4 Time Walk and 4 Ancestral Recall, since you could practically buy a car instead. The newer (and way cheaper alternative) for Time Walk is Time Warp.

But still, a deck with chronologists, echo mages and time warp are awesome in my book :)

As an example I have a green deck that focus on the sorcery Gelatinous Genesis. I mana-ramp with cultivate, llanowar elves, overgrown battlement etc. and then I throw my gelatinous Genesis spawning 5x 5/5 oozes. Beside of that I have a few Terra Stompers in case I run into alot of counter spells.

I would trim the fat: keep your favorite cards and add more of them.

For instance, take out pelakka wurm and duskdale worm and add more Terra Stompers, and do this for all level of creatures (mana-wise). So you end with with a well balanced and more reliable deck.

Also it lacks a general Idea, a few cards have landfall, some have regenerate etc. etc. In my oppinion it's better to capitalize on a general theme, and maybe 1 sub-theme. In this deck I see: Mana ramp, Auras, Landfall, Lifegain, Regeneration and even some protection. Cut it down.

would take out some of the expensive angels instead, so something like

-1 deathless angel
-1 Angelic Arbiter
-1 Iona, Shield of Emeria
-1 Stalwart Shield-bearers
+4 Luminarch Ascension

I would probably also put in some silence, for cheap lockdown against damaging spells

-3 Semblance Anvil
+3 Silence

Also sideboard some anti-flying like Gravity Well

Rise of the hobgoblins would also have great synergy with the Balefire Liege.

Also Boros Recruit and Figure of destiny (which is awesomely versatile) to have some initial 1-drops

sounds like a good plan to me. But at least sideboard hexmage, as you say, they are excellent against planeswalkers

Mortician beetle too, if you need something 1 CMC

Blade of the bloodchief and bloodthrone vampire are two excellent cards to go in a bloodghast/sac deck

Other than that it looks pretty solid

Cool combos. I just can't see it winning regularly against removal-decks. Blood seekers would also fuck up the combo ;)

So I agree with Megax9 you could do with some removal, alternatively you could also throw in some protection.

With all the walls and damage prevention I'd see good reason to use Luminarch Ascension. 4 turns of not taking damage and you will be spawning 4/4 angels for 2 mana.

Oh. Thought leveling was like other activated abilities. Well, without it some flexibility is lost, but should still work somewhat effective.

Only non-standard I got in there is Capsize, but it is pretty essential for this deck at the moment. If you could mention some nice alternatives for Capsize, please do :)