Forgotten Ancient is always a great choice. Especially in big enough multi-player games.

DeMal92 Thanks for the suggestion! I've never seen this card before, but he'll be a good addition to the deck.

I believe Gilder Bairn could be a good addition, it does the same thing as vorel but as an untap instead of a tap. I added a Gyre Sage in my list for the unlikely but funny time when both of them will be on the battlefield with Experiment Kraj

kraknoix thanks for the suggestions!

Do you know any ways of efficiently tapping the Gilder Bairn ? Well, I could buff him and turn it into an attacker...

@cian114 Oracle's Insight and the such

awesomeguy37 Oracle's Insight is terrible in Commander

I meant auras that make the creature tap for eneficial effects, not Oracle's Insight specifically.

Also Glare of Subdual

awesomeguy37 Oh, You're suggesting ways to tap the Bairn... I have considered Glare of Subdual , I run it in my Trostani deck. Opposition is similar to the glare but it also taps lands, so I might test that out for now to see how it works out.

Yeah, sorry, i didn't make that clear enough

I didn't think of Opposition but it does seem better than Glare of Subdual so by all means test it.

In my Vorel of the Hull Clade deck "Double the Rubble" (note I'm making some heavy changes atm), I use a Paradise Mantle and a Training Grounds to lower the mana cost of Guilder Bairn and to tap it for the mana it needs to use its ability. Since I'm still working on the deck I have yet to put it into full practice but from my perspective it works fine

I have considered both of these too, AntiShisno. I don't find the interactions reliable enough for EDH.

I'm gonna look for some more untap abilities...

Tamiyo, the Moon Sage is always a nice way to tap a creature, and it's somewhat funny to see a friend's face when he realizes that I just doubled her loyalty by tapping a Guilder Bairn. Then again, as I said, I have not put all of this into practice as an edh deck so anything is possible

Solidarity of Heroes For the +1/+1 counters!

AntiShisno Dang, Tamiyo didn't even cross my mind... She's definitely in!

Verzuvius I don't find the card efficient enough to be played in EDH

I don't know if you been told this or if you already know but your commander is banned in 1v1 commander games and is only allowed in multiplayer ones due to her command ability letting you flash her in for 4 mana at any time (yes this ability assentially gives her flash) regardless of how often she dies

Jamesfurrow I'm well aware that she's only for multiplayer.

Ok was making sure because i had people who didnt and i let it go and still won but i didnt want you to fall into that catagory. Otherwise id suggest rhune for your commander

Jamesfurrow I had Jenara, Asura of War as general, but I'm testing derevi because she seems to interact with the deck better than Jenara.

Ah ok no problem was just making sure ya knew that

Greater Good should get you a full hand in this deck. Glen Elendra Archmage and Master Biomancer are a match made in heaven. I suggest you find a spot for Survival of the Fittest , THE single best creature tutor in EDH I think. It also assembles your Saffi/Reveillark/Karmic Guide combo very easily.

And I've glanced quickly over the comment to see if Opposition was mentioned (and it was), this is an amazing card, and it's downright unfair if you have a Prophet of Kruphix /Seedborn Muse out. To make it truly nasty (and I realize this is way off theme) you could run Winter Orb to lock everyone down but yourself.

I never play a blue deck without a few counterspells, at least you should run Pact of Negation , if only to constantly have the threat to have a counterspell you can cast. You can transmute for it using Tolaria West , which is another great utility land you're missing out on.

Riptide Laboratory is also a must. It protects your important wizards (Teferi, Mage of Zhalfir , Prophet of Kruphix , Master Biomancer , Momir Vig, Simic Visionary ). But it can also allows you to recast Venser, Shaper Savant over and over, or Prime Speaker Zegana , and if you add it, reset Glen Elendra Archmage . In my decks, I also use it to get multiple Trinket Mage triggers or use Mangara of Corondor multiple times (but mangara without Swiftfoot Boots is very slow as you might notice).

That's all that comes to mind right now (in the counter-strategy at least, Derevi lends itself to a great number of strategies).

deathbygiraffe I'm not much of a control player, I prefer creatures. It's a personal choice of mine to have limited counterspells (my counterspells are creatures too!). I have considered Greater Good as well, for my trostani deck as well, but I just get attached to my creatures, I don't like sacrificing them. I might put in the Riptide Laboratory at some point.

Are you an Imgurian, by chance? (because of your username)

Thanks for the comment!

Well that's fine. I just like to have the option to occasionally say 'hang on' when holding a Pact of Negation I guess.

You could of course run Contagion Engine and Contagion Clasp for extra proliferation.

By the way if you add Astral Cornucopia and/or Gilded Lotus , they go infinite with Derevi, Empyrial Tactician and Deadeye Navigator , which allows you to tap and untap anything at instant speed, essentially tying up the entire board (during other people's upkeep step for instance).

deathbygiraffe I don't like the poison as mch, I pretty much just want t ofocus on my creatures getting them bigger and such. I'm familiar with the combos with Derevi, I just don't like running infinite combos.

Juniper Order Ranger is a good way to make your creatures, and himself, bigger.