Torpor Orb is the cornerstone of my Phage list and let's me run havoc on green decks that run ETB art/ench removal + Krosan Grip. Also note that it is all things that trigger upon entering the battlefield, Aura Shards included!
Worth pointing out that it doesn't have to be combat damage, so effects like Soul's Fire give infect.
Fair enough however adding these effects means you're already diluting a deck with additional spells to supplement subpar infect creatures. Skithiryx is really the only competitive infect creature outside of BSC, which I'd say is equally as game ending as similarly costed creatures (Ulamog anyone?).
Or things work out just right and you have a bunch of mana, an Inkmoth Nexus, and a Kessig Wolf Run... Sometimes it does jump up and bite you in the ass, but so do Karmic Guide locks, Living Plane locks, and any other "WTF was that! (slap!!!!)" move that we love this game for.
As you pointed out, this is a natural element of an EDH game. When playing against well tuned decks, it's quite scary how close anyone is to death at any given point in the game.
Infect is a creature mechanic that requires said creature to actually deal combat damage... You're bad at the game if you're continually not able to a creature that needs to attack to really DO anything.
I've had a fair number of end-of-turn plays where I turn someone's Cabal Coffers into an artifact and stare at the green player uncomfortably for a few seconds. It's a pretty effective strategy.
Pretty sure those were MY cabal coffers and I'm also pretty sure you used it on my turn so I could sculpting steel a coffers... #HookItUp
My Skithiryx list is LIGHTNING fast and usually ends up 3vs1-ing the table as an aggro deck. They key, just as in Starcraft II or any other RTS, is in the timings.
Playing it on turn 4 is generally terrible since you're basically skipping your turn and replacing it with either a land or a turn 5 play. You get zero board position by doing this. I'd rather play something that gives me card advantage and draw into one of the more efficient tutors or the tutors that provide multiple cards. Late game I'd prefer Increasing Ambition or Diabolic Revelation since they are a tutor with benefits.
It might be slightly better than Beseech the Queen which also sucks.
Rune-Scarred is generally only worth it in a deck where you're constantly recurring or blinking it. In a vacuum with no other support cards to abuse it's mediocre
Someone mentioned Diabolic Intent above. That one is actually quite good in the right deck. If you have tokens and/or abuse sacrifice effects it's powerful.
Mana cost matters, even in EDH. Diabolic is the most expensive black tutor that doesn't provide card advantage or replace itself. That puts it at the bottom of the list for me.
Turn 4 for coffers or something equally potent is not a waste of a turn.
I could never imagine running a mono-black deck without the following:
Vampiric Tutor
Imperial Seal
Demonic Tutor
Grim Tutor
Diabolic Tutor
Increasing Ambitions
Beseech the Queen
Rune-Scarred Demon (Assuming no Torpor Orb! #Phage.dec)
These cards will get you the win. Seriously when is mana a problem for mono-black? If four mana for the answer to your current woes is too much, you've constructed your deck poorly.
It is the opportunity cost that matters. In a more aggressive meta that 4-mana you are spending to tutor is 4-mana not being spent to advance your game or disrupt someone else's.
Personally I think it is fine as a budget option for decks that really need the tutoring effect for a combo set up or silver bullet, but wouldn't run it outside of that situation. In my black decks I would rather just draw 3 cards for the same price.
I play it in the most aggressive Skithryx list that the EDH world has ever seen and it has never disappointed me. I cast it many times on turn two, ideally off a dark ritual with an LED in play
If you're playing mono-black, you have no reason not to play it. There is no such thing as too many tutors. They give you options and mana is rarely a problem in a well built deck.
Xiahou Dun and Sheoldred both are better as part of the 99 I feel.
Fair enough however adding these effects means you're already diluting a deck with additional spells to supplement subpar infect creatures. Skithiryx is really the only competitive infect creature outside of BSC, which I'd say is equally as game ending as similarly costed creatures (Ulamog anyone?).
As you pointed out, this is a natural element of an EDH game. When playing against well tuned decks, it's quite scary how close anyone is to death at any given point in the game.
Pretty sure those were MY cabal coffers and I'm also pretty sure you used it on my turn so I could sculpting steel a coffers... #HookItUp
Turn 4 for coffers or something equally potent is not a waste of a turn.
Vampiric Tutor
Imperial Seal
Demonic Tutor
Grim Tutor
Diabolic Tutor
Increasing Ambitions
Beseech the Queen
Rune-Scarred Demon (Assuming no Torpor Orb! #Phage.dec)
These cards will get you the win. Seriously when is mana a problem for mono-black? If four mana for the answer to your current woes is too much, you've constructed your deck poorly.
I play it in the most aggressive Skithryx list that the EDH world has ever seen and it has never disappointed me. I cast it many times on turn two, ideally off a dark ritual with an LED in play
Tutors get you what you need to win.