The whole idea of the sort-of-mono-blue Blazing Shoal deck was to have:
Blighted Agent 
or
Inkmoth Nexus 
on the field and cast
Blazing Shoal 
but instead of using
you cast it for its second cost removing either
Progenitus 
or
Dragonstorm 
from the game to swing for lethal infect turn 3. Since you only need to cast blue spells it only has blue mana access but at the same time has a number of big red spells to sac for
Blazing Shoal . It can theoretically win on turn 2 with little or nothing your opponent can do about it. Hence banning.
100th post 29/01/12
500th post 19/05/12
1000th post 19/07/12
How many planeswalkers does it take to screw in a lightbulb?
Spoiler:
Show
Better question, what does Nicol Bolas want with the lightbulb?
