Continuing with my renaissance of combo in the cube I decided to build an old classic in Severance Belcher. Historically I have not had much joy with this combo in the cube as, like Erratic Explosion, it tends not to kill people when you go off. This is because in a 40 card deck you have run your library too low on cards to deal enough damage by the time your Belcher is on-line. Belcher has the advantage over Erratic Explosion in that you get to do it again once you untap it and have mana but does cost a great deal more to cast and use. To tackle the problem of having too few cards once I was able to use a Belcher for the kill I decided to splash red for Mountains. This would allow me to leave a single Mountain in the deck after casting Mana Severance which gives you a good chance to kill in one hit when you have less than twenty cards left in library. I did get rather over excited with this plan and added things Like Sleight of Hand to live the dream and put my single Mountain on the very bottom. Needless to say this didn't happen and I shouldn't have played the weak spells.
Typically the deck is blue black so as to utilize tutors and targetted discard from black. This makes the deck far more robust as the targetted discard in black is one of the cheapest and most effective ways to deal with problems and disrupt in combo and redundancy in tutors is great. Yawgmoth's Will also helps to recover if they should deal with the Belcher which blue can only do via a Timetwister effect. Having seen the benefits of having access to mountains in the deck I would not do it again without them but it would be pretty easy to incorporate black with that as well. This is basically a mono blue build of the deck as going much deeper into red doesn't offer very much and starts to really harm the mana base. I felt I could get away with so few lands given the high number of one drop cantrips and the single colour requirement. I would likely have to run an extra land or two if I was going to go UBr or UR rather than Ur.
Sensei's Divining Top
Sleight of Hand
Into the Roil
Fire / Ice
Tezzeret the Seeker
City of Traitors
Seat of the Synod
Other considered cards:
Elixir of Immortality
The disruption I played in the absence of black included Remand, Arcane Denial, Into the Roil and Spellskite which is light but gives a nice spread. They are all quite wide application and offer you more cards or good insurance. The Spellskite in particular is a fantastic card in most combo decks as it holds off early pressure quite well and later protects many combo pieces. Also helping out with things to Tinker, Welder or that need metalcraft.
This is still a tricky deck to play as most combo decks are but compared to many other cube combo offerings Severance Belcher is one of the simpler and more robust ones that you can build. Not needing to use creatures as part of your combo is one of the best ways to avoid the worst disruption in the cube, a good rule is if you can't beat Swords to Plowshares / Path to Exile or a Lightening Bolt without great effort then your combo is too fragile. Although not among the most broken combos in the cube it is in the top tier along with them and uses no banned cards or much at all from the B cube. Goblin Charbelcher is not unusable outside of combo decks too so it is a worthy combo if any to make an option in any cube. It is also the first of the recent combo decks I have built that I managed to win all my games with, even despite some horrible misplays.
No land Belcher is an alternate way to try and use the Charbelcher to kill people instead of trying to find a mana severance. These decks use things like Harrow, Nature's Lore and Farseek to pull the few (about 6 total) lands out of the deck and things like Lotus Petal and Elvish Spirit Guide to ensure you have the mana to cast those cards. It is a harder deck to build that the one using Severance and can be almost any mix of colours with green giving more options too. It makes up for this by being a little easier to play although unsurprisingly quite similar.