Heritage Reclamation The only common that manages to slip into my list is Heritage Reclamation, a card thats flexible enough
If the average price somehow increased to $3, it would be profitable to just crack boxes (and even more profitable than usual because there's no risk or variance, since the basic land is guaranteed in every pack)
The value of X is calculated only once, as Eldrazi Linebreaker's last ability resolves
In Limited, this could be a late-game finisher, but it requires a critical mass of Room cards to be truly effective
(If a permanent with a stun counter would become untapped, remove one from it instead.) Whenever you tap one or more untapped creatures your opponents control, draw a card
One thing strongly in the favour of Forbid in the cube as opposed to any other format is that there being only one copy of any given card there is quite a sharp tail off in the quality of groups of spells