You might consider Conjurer's Closet to keep bouncing a scarecrow and destroy an extra permanent.

I have a Reaper King EDH deck that I rarely play with my playgroup anymore because they hate it so much haha. It was the first deck that I built and I've gotten a lot of play experience with it, and I have a few words of advice:

First off: Master Transmuter. I can not stress enough the incredible power of this card. Having trouble getting the mana for that Darksteel Forge? No problem. Need to destroy another permanent? No problem. Need to save your Reaper King from that kill spell you know is waiting? No problem. How about infinite mana with Gilded Lotus and Freed from the Real? Done. A must have for any deck like this.

Secondly: Deadeye Navigator. He get's ugly fast. Bond with Grim Poppet after dropping the King and watch your opponents cry.

Thirdly: Birthing Pod. Downright awesome for pumping out those better Scarecrows. Not to mention Reaper King's CMC is 10. Fourth turn Ulamog, the Infinite Gyre anyone?

Fourthly, good in any 5-color EDH: Bloom Tender. I have killed so many people with just this one card it's ridiculous. Do a bit of acceleration drop it before you drop Reaper King, then tap it for five, drop Gilded Lotus into Manalith into Sol Ring (by the way get a Sol Ring) into Doubling Cube (get that too), and your looking at ~36 mana turn 4 or 5.

Lastly I'd just like to address your land base. There's no way you run this deck with 28 lands, with many that enter play tapped, and so few accelerators. I would increase your land base, maybe get a Cavern of Souls (if you can afford it), and include some basic lands so you can use some of the amazing acceleration green has to offer, Harrow, Journey of Discovery, etc... And if your going down the "I don't like basic lands" route, go for some Ravnica shock lands and some Zendikar/Onslaught fetch lands (Expensive but hey). Really good for this many nonbasic lands is Amulet of Vigor. I'd also like to add that I've had limited success with the artifact lands. You don't have much in the way of Affinity, so they are totally pointless and horrendously easy to destroy. (Getting a land Naturalized sucks).

Overall I really love the deck and it's ideas. Just needs a few tweaks. Your inclusion of Vengeful Rebirth makes me very happy. It's a very underrated card that I have used since the beginning of my Reaper King deck to recurse anything from Time Stretch to Reaper King Himself.

"It's Harvest Time". Keep up the good work. +1

Thanks for the suggestions all. Unfortunately, the biggest limiting factor to a good number of them is the cost (limited budget and all), but I've written down a fair few of these to look for. Oh, to have more disposable income. Definitely going to be looking for Conjurer's Closet, Amulet of Vigor, and Master Transmuter. Cavern of Souls is definitely on my wishlist.

Glad to hear someone else has successfully run the Reaper King as an EDH general.

Tezzeret, Agent of Bolas I feel should be mandatory in nearly any artifact deck, if he survives 1 round he's pretty much a win-con

Hi, saw your forum post, here are some land suggestions you may like to review:

Try the tripple bounce lands: Dromar's Cavern , Treva's Ruins , Crosis's Catacombs , Darigaaz's Caldera , Rith's Grove

The triple tapped versions: Seaside Citadel , Arcane Sanctum , Crumbling Necropolis , Savage Lands , Jungle Shrine

The tripple filter lands: Aysen Abbey , Wizards' School , Castle Sengir , Koskun Keep , An-Havva Township

The dual filter lands: Darkwater Catacombs , Mossfire Valley , Shadowblood Ridge , Skycloud Expanse , Sungrass Prairie , Fire-Lit Thicket , Graven Cairns , Mystic Gate , Sunken Ruins , Wooded Bastion ,Cascade Bluffs , Fetid Heath , Flooded Grove , Rugged Prairie , Twilight Mire

Most of those are all well under $5, most under $2.