Find out how to throw a thumber including the different kinds of grips, how to practice throwing thumber, when to throw it and when not to and some tips for the thumber.
An article discussing the finer points of the thumber is available here: Throwing a Thumber
In Europe we have indoor games that are totally different from what most North Americans play (I understand you mostly play indoor on artificial turf). We have indoor which is played on a hardcourt field, about twice the size of a basketball court. In this type of game the faster and higher throws like blades, scoobers, thumbers and hammers are extremely valuable.
I wouldn't throw a thumber in an outdoor game though, since they tend to be less accurate (due to being thrown quickly after catching) and they're susceptible to the wind a lot. But it is a fun throw to practice!