Oreskos Explorer replaced by Knight of the White Orchid

Blink still needs better support, and Knight of the White ORchid puts lands onto the battlefield while Oreskos Explorer does not.

With this update I'm adding several new cards from DMU and the 40k Commander decks. I'm also switching out several cards to improve the UB Ninjas deck.

LEGEND CHANGES
Rhys the Redeemed replaced by King Darien XLVIII
The token-making abilities of Rhys are powerful, but a dedicated token deck has no shortage of ways to make tokens, making Rhys redundant and unappealing. King Darian cannot produce tokens as easily, but the utility he provides is invaluable to token decks and should play nicely to make token decks more resilient and threatening.

DMU CHANGES
Hero of Bladehold replaced by Defiler of Faith
Hero of Bladehold's reliance on attacking prevents it from building a large board. Additionally, the tokens and Hero itself are easily picked off by blockers Defiler of Faith will be a more consistent token maker and provides a strong mana advantage for white heavy decks.

Cloudkin Seer replaced by Aether Channeler
While Aether channeler may not be as synergistic with ninjitsu, it is a strict upgrade in every other way.

Font of Magic replaced by Haughty Djinn
Font of magic is very slow and often only gives a single mana discount. Haughty Djinn is cheaper while adding an evasive threat and good blocker.

Blood Artist replaced by Cult Conscript
Blood Artist is intended for the WB sacrifice deck, but slots too easily into any black deck. Cult Conscript provides a repeatable sac target, something the WB deck is currently missing.

Imperious Perfect replaced by Leaf-Crowned Visionary
Visionary provides an incredible draw engine for the Elves deck and keeps the anthem of Perfect.

Sword of Hearth and Home replaced by Golden Argosy
The sword was meant to be a payoff for the WU blink deck but is too easily playable in other decks. Replacing it with a more powerful, but narrower, blink engine should help WU come together more consistently

40K CHANGES
Kor Cartographer replaced by Space Marine Devastator
Kor Cartographer is a payoff for WU blink, but four mana is too much, even when blinked. Space Marine Devastator cements white as the best removal color and still synergizes with blink, while also having synergy with the WG tokens deck.

Territorial Kavu replaced by Atalan Jackal
Territorial Kavu doesn't do enough to justify its inclusion, and domain plays poorly in a commander cube. Atalan Jackal is much more in line with RG's landfall strategy.

UB Changes
Thousand-Faced Shadow replaced by Prosperous Thief
While Thousand-Faced Shadow is a cool card, getting its ability to go off is rare, and it ends up being a dead card. Prosperous thief works by itself and with other ninjas, making it a much better payoff.

Vampire Nighthawk replaced by Necropolis Regent
Nighthawk was included as a way to consistently get ninjitsu triggers but doesn't do enough to justify itself. Necropolis Regent acts as a win condition for the ninja's deck, allowing unblockable creatures to get massive and start eliminating players.

Moonsnare Specialist replaced by Reconnaissance Mission
Bouncing one creature isn't enough for the setup requirement here. Reconnaissance mission gives the UB deck more draw tools to keep pressuring opponents, and cycles in a pinch.

Murderous Rider replaced by Plaguecrafter
Murderous rider has no synergy with the rest of the cube. Plaguecrafter works with aristocrats, reanimation, and even blink, and feels much more at home in the cube.