i would move moltensteel from maybeboard to mainboard. you can pay as much as you have available in red mana to boost it, then pay life to get up to 21 commander damage in one hit.

Conspiracy is super good for this guy, it makes everything you want dragons and then every creature in here is potentially viable for the avatar state.

Draco as you don't have to pay the upkeep cost.
Scourge of Valkas for big Patriarch's Bidding

If u want to check my deck, Ur-Dragon's legacy I'm writing my toughts about the deck, and I gladly listen to others opinions.Example: Draco have a good sinergy with Spellbound Dragon and Hoard-Smelter Dragon , and the combo Karrthus, Tyrant of Jund + Patriarch's Bidding is just amazing.

I run a Scion deck and I've recently added Conspiracy - so, for the lols, have added Progenitus ... He's a dragon, right?

Oh, and Training Grounds to make Scion's ability cheaper

Progenitus does look like a dragon, but is actually a hydra avatar.

That uh... That was a joke about Conspiracy .

I thought too about Training Grounds , but it is not so effective, in the end.

If you have 4 mana and more than 12 life you can win on the spot. Attack and if not blocked, make scion into moltensteel dragon, pay 12 life and stack the fire breathing triggers, before they resolve make scion into skithryx , the triggers resolve and you hit for 10 poison

Please check out Fire and Blood (pure dragon tribal deck) it might help you build the commander deck you are hoping to create.

Please check out my commander deck build. It has a similer build as this one, but more focused on regen. Scion of the Ur-Dragon - Dragon/Regen Thank you!!!

Mistveil Plains combos with scion.

And it's even a Plains for easy fetching. Thank you very much!

I agree with comment #35 above. Moltensteel Dragon needs to be main board. Easily one of the best cards in my Scion deck.

You may want to consider more of the Sarkhan cards, especiallySarkhan Unbroken.

+1 cuz Dragons!!! lol, i like what youve put together here, ive been working on a scion deck too for the past couple of months, but i didnt go full on reanimator, im only running 1 reanimate spell (aside from the dragons) in Patriarch's Bidding. if youd like to, id appreciate it if you checked it out. Dragon Armor (Scion EDH) i take any and all criticism. but with your deck, i can only suggest a Liliana Vess ultimate effect, if not liliana herself, maybe try Rise of the Dark Realms? could work out for you.

I know it goes against the whole dragon theme, but Conspiracy combos with Reya Dawnbringer to start bringing back all your Scion'd dragons.

Also, I normally play an angel EDH and have been trying to make a re-animator Scion deck for a while. It's just one though I've had. But looking at your list makes me want to stick with just dragons.

I know you said you were avoiding conspiracy tricks, just wasn't sure if you had thought of that one.

Are your edh games usually very long? Cause otherways I can't see how you cast all that mana expensive sorceries...

If I'm playing against more than one opponent (which is what I usually do) then yes, my games do take quite a while to finish. If I only have one opponent then I need to have an impressive Plan B if the main strategy of winning with Scion doesn't work. In that case, the game is probably also going long. Also, only 3-4 of those spells cost more than 5 mana (Beacon of Tomorrows, Time Stretch, Villainous Wealth, sometimes Earthquake), and 5 mana is the magic number my deck is shooting for in every game anyway.

It make sense. Well, I have an EDH deck too, and I use a different philosophy from your, so I will not comment any further but... I think you have to add for sure something to protect your Scion. Dragons like Silumgar, the Drifting Death and Dragonlord Ojutai can save your Scion with hexproof, or even be used as attack utilities.

Thanks. I want to add both of those cards (among others) but I haven't had time lately to sit down with my deck and look through everything. All of my Commander lists on Tapped Out represent something I actually have built in real life, and I try to keep them synched up as best I can.

Check out mine Scion Dominate

First of all, have you considered any of the dragonlords from Dragons of Tarkir? My brother runs Dragonlord Ojutai and Dragonlord Dromoka in his Scion deck and they both seem really useful (and they both look sweet). Second, you should replace Darksteel Ingot with Chromatic Lantern. In my experience, having a rock that allows your lands to tap for any color is much better than having one that's indestructible, and I never play more than three colors. In five colors, Chrome Lantern would be even better. Or you could try Prismatic Omen. That would work well with that Draco card in the maybeboard, and it seems more useful than Mana Bloom.

What about switching out City of Brass with Command Tower. Maybe switch something out for Nykthos, Shrine to Nyx.