the strategy is this. there is a local tournament and i know that the ppl who play on it have problems with configuring tactics so they just use the one thought inpenetrable. aka cascada of battlecruisers,carriers or guardians+mutalisks...

How to crack it down?

Advantage: They can wipe out your entire army, base, defence or offence in just minutes with the mass power they have in countless units.

Disadvantage: Only a pro can control mass army and more to watch every aspect of it. Most noobs just see the fire power those units commense, not the tactics they can do with them.

My tactic:

Terran: Medic's optical flare can permanently destroy detector ability only if you are playing against another terran and he to abolish ur effect. Few medics should cover up this. Detector must be in sight if you are playing against protoss, to see their observers. Make few dousins of ghost teams and lock em down. Next nuke the area and charge with ur attack team to eliminate them.

Protoss: Few dark archons should cover the mind control ability over their detectors, many are needed if an enemy has many overlords. Bring arbiters with corsairs or scouts and dragoons to vanish the air assault team. Corsair's ability can make the enemy un-available to shoot so bust few clouds of emp near it to completely decay their attack.

Zerg: Need advice here.