It’s quite possible that you might end up having Guttersnipe and plenty of support for it in a Limited deck. Maybe you put in Launch Party for some removal, and the time comes that you have to cast that Launch Party with your Guttersnipe as the only creature you have on board. In such a situation, your Guttersnipe won’t trigger; you have to sacrifice your Guttersnipe as a cost, so by the time the spell is actually considered to be “cast”, the Guttersnipe is dead and the trigger won’t trigger.
The casting process has several steps, the last of which is “pay costs in any order.” It’s only AFTER that final step is completed that the spell is actually considered “cast” for purposes of triggered abilities, and at that point, the Guttersnipe is already in the graveyard because you sacrificed it while paying the aforementioned costs. The trigger condition wasn’t met for its ability before it was sacrificed, so you won’t get that 2 free damage you may have been hoping for. Sorry!
Today’s Rules Tip written by Trevor Nuñez