Using specials?

[Szei]

Exactly what Art said. Special units certainly aren't desperation units to use in situations like when you're runner rushed. Rather, I find myself using them to break stalemates when both sides have 4-5 units on the same side of the board (note the 'same', not total). The bombshell can then be used to break your opponent's formation by entering siege mode near them and forcing them to separate their units lest they take a ton of splash damage. Forcing them to break formation can often put them into a vulnerable position or at least a less favorable one which you can then capitalize on. Alternatively they won't move either because they didn't scout your bombshell or because they don't have enough wits and you'll dish out a ton of damage.