unending amounts of marines out of many many many barracks once you get you economy going. It's a slow strat, easily beaten if you know it's coming and expensive as hell. It also only works on money maps once you get your economy going. It's merits are that vespene cost is very low(a few hundred is all you need for the upgrades), marines can hit anything, ground or air, terrans have the scanner so they don't need to keep observers around, and it only costs you in minerals, which most people can set up a mineral based economy fairly easily. Also, you get offensive units very quickly. It's quite a site to see, marines dying, just to be replaced by more marines out of a bagillion barracks. Carrier whores are particularly vulnerable to this because that many marines destroy the interceptors in seconds and, for the most part, turtle up and give the player plenty of time.
I think M&M (medics and marines) has pretty much replaced it tho.
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