

commander · Abaddon the Despoiler
The Ruinous Powers (40K).
A Grixis chaos and cascade deck led by Abaddon the Despoiler, cast spells with the mark of Chaos to cascade freely and unleash the four Chaos Marks for escalating effects each time you cascade.
The Commanders
The Ruinous Powers is a Grixis Commander deck themed around the Chaos Space Marines of Warhammer 40,000. The hook is "mark of Chaos": spells with these marks cascade when cast, and the four Chaos Gods each give you a bigger payoff the more you cascade. Abaddon leads a deck that spits out free spells off nearly everything you cast, and it builds toward a cascade chain that empties your hand in one turn.
Abaddon the Despoiler has trample and cascade himself, plus a second ability: spells you control with one or more Chaos marks have cascade. The deck is full of 40K-exclusive spells carrying marks of Tzeentch, Nurgle, Khorne, and Slaanesh. With Abaddon out, every marked spell cascades off its mana value. Cast a seven-mana marked spell and cascade into another marked spell which cascades again. The chain continues.
Be'lakor, the Dark Master is the shadow-play alternative. He makes all Demons you control have menace and draws a card whenever a Demon enters the battlefield under your control. Against creature-heavy pods, Be'lakor's flying Demon army with menace is nearly impossible to block profitably. He also transforms the Chaos Daemon tribal theme into consistent card draw.
Key Cards
Mortarion, Daemon Primarch
Mortarion has flying, trample, and a mark of Nurgle, so he cascades when cast with Abaddon. More importantly, he has a triggered ability: at the beginning of each end step, put a -1/-1 counter on each creature you don't control. Over two or three turns, Mortarion shrinks and kills every creature on opposing boards. Pair him with Abaddon's cascade to get him in for free off another spell and start the attrition clock right away.
Magnus the Red
A legendary 7/7 flying Demon with a mark of Tzeentch that cascades with Abaddon. He copies the first noncreature spell you cast each turn. Pair Magnus with any strong instant or sorcery and get a free copy. Cast Blasphemous Act with Magnus out and double the board wipe. Cast a cascade trigger and the copy cascades too. Magnus's copy ability hits hardest in the late game when you cast high-value spells every turn.
Mandate of Abaddon
A 40K exclusive sorcery with all four Chaos marks. Each player sacrifices all but the greatest number of permanents they control among any of their permanent types. Read that again: for each permanent type, keep only the most of any single type. Players sacrifice down to their best cluster of permanents. With all four marks, this has cascade with Abaddon. Cascade into Mandate and wipe opponents' boards for free off a larger spell.
Blasphemous Act
One red mana once enough creatures are in play to cut its cost to one. Deals thirteen damage to all creatures. In a deck built on cascades, Blasphemous Act can show up for free off a larger spell's cascade. It clears opponents' creatures while your Demons, which cascade with Abaddon, stay backed by Be'lakor's body count. Thirteen damage kills most commanders and nearly every creature without indestructibility.
Drach'nyen
A legendary Equipment from the 40K set. It gives the equipped creature +2/+0 and cascade whenever it deals combat damage to a player. Equip Drach'nyen to Abaddon himself and each attack throws a cascade trigger. Abaddon already has cascade plus the marked-spell cascade. With Drach'nyen, every attack step cascades a third time. That's three free spells per attack, each one firing off the others' marked abilities.
How to Play
Get Abaddon down as early as you can, since his cascade on marked spells is the engine that makes the whole deck work. Bring in Be'lakor as backup if Abaddon keeps getting removed, turning the Demon tribal suite into card draw. Use the cascade chains to drop Mortarion and Magnus for free off larger spells and build a board opponents can't attack into profitably.
You win by attacking with Abaddon and Drach'nyen, cascading three times per attack and chaining into Blasphemous Act or Mandate of Abaddon to clear opponents' boards. Mortarion's end-step -1/-1 counters clock the table while your cascade chain builds your own. The deck is at its best once Abaddon has been online for two or three turns and each cascade chain becomes a three-for-one or four-for-one.