Mulligans
General Mulligans
The Dark Portal is obviously a keep. Even two of them. They are your quickest way to victory. As I said in the guide, Dark Skies is your most consistent board clear in the early game, so you may decide to keep it alongside The Dark Portal. However, I would recommend mulliganing very aggressively for your Portals.
Of course you want to always mulligan away all your dragons, as this messes up the Portals.
Aggro Mulligans
If you're facing very aggressive decks, you may want to keep some of the above. Sacrificial Pact is especially valuable against Demon Hunter.
Control Mulligans
In control match-ups you should always mulligan aggressively for your Portals. However, if you already have one in your starting hand you can keep a Twisted Knowledge, as this card can win you value wars single-handedly.
This deck started out as a just-for-fun Malygos list, but after a few games I realised it had potential! I’ve been playing it in Legend with a decent win rate, even when facing top tier decks.
The deck is an extremely spell heavy deck. It only runs three minions, namely Malygos, Alexstrasza and Zzeraku the Warped (although Zzeraku can be swapped out for Onyxia ).
The plan of the deck is to tap in the first few turns and play The Dark Portal as soon as possible, in order to cheat out one of your big dragons. If you have the coin you may even play The Dark Portal on turn 3 and play your big dragon on turn 4. 
In the best case scenario, you cheat out Alexstrasza on turn 4, draw Malygos on turn 5 through another The Dark Portal while smacking your opponent in the face with Alex. On turn 6 you can play Malygos and one or two cheap spells like Soulfire or Nether Breath, for some huge burst damage.
If you don’t draw your The Dark Portal, worry not! Play the deck as a classic control Warlock. There are many cards that can help you control the board and heal through your opponent’s threats. Dark Skies is your most consistent control tool, but Rafaam's Scheme and Plague of Flames is a powerful combo too.
Thanks to the abudance of removal you’re likely to reach the end game, which where you want to be. However, this deck wouldn’t be as consistent if it wasn’t for Plot Twist . Say you don’t draw your Portals and not many removal cards. You can cycle your whole hand through Plot Twist to look for that removal spell you’re looking for. In many cases Plot Twist provided me with the out I needed, in very close games. Plot Twist is especially effective since all your spells are relatively cheap. 
Another honorable mention is Sacrificial Pact that can work as a powerful tech against Warlocks and Demon Hunters but also synergises well with Rafaam's Scheme or any demons you may pull from Twisted Knowledge , if you’re desperate for a last minute heal. Speaking of Twisted Knowledge, it’s extremely powerful in control match-ups, sometimes providing continuous value through discovery effects; or simply as a hand enlarger for your The Dark Portal in the early game. Should the game go to fatigue, it can even provide protection from fatigue damage if you manage to use Plot Twist to shuffle your larger hand back into your deck.
Lastly, let’s talk about Zzeraku the Warped. You could do with just Alexstrasza and Malygos, as these are the essential pieces in the plan. However, adding a third big minion helps to prevent the Portals from bricking in your hand. If you don’t own Zzeraku, you can swap him out for Onyxia. Onyxia can fill the board quite nicely in the early game and of course has synergy with Nether Breath. In case you were looking for a very cheap substitution, you can try with Twin Tyrant or Evasive Drakonid.























Have played about 10 games with your list (no changes) and I found it not only fun, but also competitive.
Zzeraku the Warped is insane when played on turn 5/6 thanks to The Dark Portal. It swings the balance on board if paired with Rain of Fire or hp and acts as a soft taunt, gaining 1-2 turns if your opponent can’t remove it with a spell.
Nice deck, mate. Maly decks shall rise again!
Thanks, buddy! 😀 Glad you enjoyed it.
If you want you can check out a sample game I recorded, here: https://www.youtube.com/watch?v=zlyondqVAcs