The core strategy for this deck is to make a big Karlov of the Ghost Council then smack your opponents down. The more 'gain life' instances there are in play, the faster counters will build up on Karlov.
To that end, cards like Soul Warden and Soul's Attendant, and to a lesser extent Authority of the Consuls and Bloodchief Ascension, are great to have in hand for turn 1. Assuming you will be able to play a form of recurring life gain within the first 3 turns, Karlov should be played turn 2. If the starting hand is slower (in terms of life gain), hold off on playing Karlov.
Once life gain triggers start reliably going off, Necropotence, Phyrexian Arena and Dark Confidant are good tutor targets to maintain tempo. Necropotence is definitely the strongest out of the 3 but be cautious of putting yourself in a bad situation if your life gain engine isn't strong enough to support frequent use. Phyrexian Arena edges out Dark Confidant in terms of gain vs cost, however Dark Confidant + Sensei's Divining Top
is stronger than Arena.
This deck relies heavily on Grand Abolisher when playing against control matchups. Lightning Greaves, Phyrexian Reclamation, and Sheoldred, the Whispering One can help ensure Abolisher sticks around.
This deck suffers greatly against fast token decks like Krenko, control/combo decks like Tasigur, and infect. Board wipes followed by Elesh Norn, Grand Cenobite while they rebuild takes care of tokens, Grand Abolisher and Leyline of the Void + Rest in Peace
answers Tasigur, and an early Umezawa's Jitte can help against infect. Quick kills can be achieved with Beacon of Immortality + Tainted Remedy
.
Kambal, Consul of Allocation and Sunscorch Regent are very powerful cards in this deck and will put in a lot of footwork towards victory. Regent especially offers great life gain coverage as most opponents will cast at least one spell a turn. The best part is if removal is played to remove either creature, it counts as another life gain trigger first, resulting in a bigger Karlov.
If Karlov cannot be played for whatever reason, Archangel of Thune is probably the next best threat if you have a life gain engine growing; however if you have to tutor to get the Angel, that tutor is probably better spent on getting removal for whatever is keeping Karlov out of play.
Alternative play options include:
Either card holds it's own in this deck, both having very beneficial life gain synergies, but together they create an infinite combo that drains all opponents life. Sanguine Bond can be subbed for Vizkopa Guildmage.
With Tainted Remedy on the board, Beacon of Immortality can instantly drain target opponent's life. Because of Beacon's 'shuffle into library' clause, a quick tutor can allow you to do it again.
This deck runs enough cheap enchantments that playing Daxos early and racking up experience counters can offer a great supply of cheap, big beaters.
The only life point that ever matters is the last one. Put that theory to the test with Unspeakable Symbol. If Aetherflux Reservoir is unavailable, this is a good outlet for all that life you've (hopefully) built up. Note that it's ability can be used at instant speed, which can allow for use as a combat trick.
This card lets you use life to kill people. The life gain effect isn't used to it's best in this deck, but it does trigger frequently enough that it can help make Karlov huge.
Weak Cards/ Candidates for replacement
Since it is a very strong card, with a reputation that tends to precede it, few players will knowingly give you a Rector trigger. There are also very few sac outlets in this list, making for unreliable Rector usage. Despite that, this deck tends to have a heavy reliance on enchantments, and Rector has often paid off in a pinch.
