Made an existing budget deck archetype better; creating an overall faster, harder to counter, more consistent and competitive Commander deck. Partial credit goes to the designer of the original budget combo deck that this deck is based on.
I did add some expensive things to help with consistency issues, so it is for all intents and purposes, no longer a budget deck. I updated the deck recently after discovering Sidisi, Undead Vizier is better at doing what Maralen does.
The changes I made are legit: added Lotus Petal and Dark Ritual to get main deck combo off right away, Lake of the Dead and Boseiju, Who Shelters All, as well as 3 strong Ad Nauseam sideboard combos, and mana ramp cards that allow you to use any of the main deck or sideboard combos right away. Also added optimal sideboard cards to assist in consistency game to game.
Generally speaking, save Lotus Petal and Dark Ritual for after you cast Ad Nauseam, so you can combo off in one turn.
Main Deck Combo:
Ad Nauseam -> draw deck for 6 life
Lotus Petal (tapsac for a B,) + Dark Ritual (-B, BBB,) Dark Sphere, + Sickening Dreams (-1B discard 40 cards,) -> tapsac Dark Sphere targeting Sickening Dreams (taking only 20 damage, while you kill everyone else at 40 in one shot.)
You can realistically discard around 64 cards or so, tapsac Dark Sphere, and you only take 32 which puts you at 2 life, but can kill lifegain decks at 70 or less life; so thats pretty cool.
Additionally, if you are able to use Lake of the Dead on the turn you combo you have extra mana for dropping your combo right away. Sometimes you want Boseiju, Who Shelters All and/or Lake of the Dead online before you cast Ad Nauseam. Try and use Maralen of the Mornsong or mulligan for these against blue control decks, to ensure you get your Ad Nauseam off and/or have the extra mana for your combo.
Keep in mind, if you use Boseiju, Who Shelters All to cast any spells or if you take any damage from opponents, you will need to factor that into how many cards you discard to Sickening Dream.
Sideboard Combos:
All sideboard combos cost 8+ life in addition to the main combo. The (+) is for any additional sideboard cards you add to handle opponents decks' counter-strategies.
With Lake of the Dead in play, the turn you combo after using Ad Nauseam to draw out your whole deck, you have extra mana to cast Duress, Cabal Therapy and/or Imp's Mischief to help you dodge counterspells.
Zombie Army:
Ad Nauseam -> draw deck for 8+ life,
Lotus Petal (tapsac for a B,) + Dark Ritual (-B, BBB,) Zombie Infestation (-1B, discard 80 or so cards.)
Raise a fearsome army of 40 or so 2/2 Zombie tokens to destroy all of your opponents on your very next attack phase. This is the only sideboard combo that doesn't require additional rituals to pull off, and thusly is sort of the second main deck combo.
Skirgesanguinate Combo:
Ad Nauseam -> draw deck for 13+ life,
Lotus Petal (tapsac for a B,) + Dark Ritual (B, BBB,) + Culling the Weak (-B, sac Maralen of the Mornsong, + BBBB,)
+ Skirge Familiar (-4B, discard 42+ cards + B x42+,) + Exsanguinate (-42BB+, each opponent loses 42+ you gain 42+ x how many opponents)
OPTIONAL
+ Ornithopter (in case they kill your Maralen of the Mornsong and prevent you from casting Culling the Weak)
+ Rain of Filth (-B, Sac lands + BB+,for casting other sideboard cards.)
HelmVoid Combo:
Ad Nauseam -> draw deck for 15+ life, Lotus Petal (tapsac for a B,) + Dark Ritual (B, BBB,) + Culling the Weak (-B, sac Ornithopter, +BBBB) + Cabal Ritual (-1B + BBBBB,)
Leyline of the Void (-2BB,) + Helm of Obedience (-4, -1 tap, mill target players entire library; they die on their next draw phase)
OPTIONAL
+ Rain of Filth (-B, Sac lands + BB+,for casting other sideboard cards.)
Mills only one opponent at a time - due to targeting and tapping. Having this combo vs graveyard combo decks is ideal as Leyline of the Void doubles as grave hate.
Handling problamatic permanents is a breeze with part of your combo going into using Avarice Totem to stack activations. 1 CMC for low Ad Nauseam damage, and highly effective with Skirge Familiar for stealing opponents' entire non-land board(s).
IMPORTANT
Don't use the HelmVoid combo vs stuff like Kiki/Splinter Twin combo decks, as you will need Ghastly Demise, and with Leyline of the Void in play, you won't likely have enough in the grave to handle their combo pieces
