Hello everyone.

1. Explanation of the deck : 

The main point of this deck is to cycle your library constantly with on board + wich give you a mini dovin ult, giving access to whatever you need to control the opponent.
, and are keys of the deck to cycle your graveyard.
Basically, you control the first few turns of your opponent with , , and for aggro decks, and when you get to + , you start cycling and playing until death. 

Strength of this deck is to be very constent, and unmillable. you actually win a lot against others control decks just by mill, and you win against aggro by goin' face with an unkillable Lich and Krasis.
MidRange decks can be a problem sometimes, but goin' in Bo3 you will be able to handle it easily.

2. Thoughts and improvments:

I actually made this deck, surprisingly running pretty well against the meta. 
However, I'm still looking to improve it as a true sultai control deck, based on the combo Krasis+Lich for the draw engine, wich can be a reliable way to do a dovin's ult often times (like for 8 mana for krasis + underrealm lich on the board, you actually dig 9 cards into your deck to draw 3.)
I really like this combination, adding some meat to the control metagame, with an alternative win for planewalkers, but still not sure about the construction of the deck itself. 

I sometimes need more wipe board, sometimes need more counterspells. 

I recently added font of agonies instead of wilderness reaclamation, wich doesn't really fit due to the lack of instants, it is just strong after a krasis turn. *Edit* : After fue games running font of agonies, I went back on 2 sinister sabotage and 2 wilderness reclamation, it is way stonger .

Let me know what do you think about it, try it, can work on bo1 and really strong in bo3, and tell me what would you do for this deck to be better. 

Peace everyone !

Edit: You can argue on replacing frilled mystic for negate or sinister sabotage for the mana curve, but I think frilled mystic is a bit of meat who can block and maybe sometimes go for 3 damage in the face, tell me if I'm wrong! 
Edit 2 : Due to the curve, frilled mystic goes bye bye, replaced by 2 sinister .