Three clicks each
The first O drifts in from a corner and you think this is manageable. Then four more arrive. Each one takes three hits and the ring around it thins as you land them, so you can see how close a kill is, which is exactly the information that makes you greedy and lose two blocks somewhere else.
They go for whatever is closest. The long result blocks take the longest to chew through, so the tab row and the footer links usually disappear before you notice they were being eaten at all.
The counters
Kills is obvious. APM is actions per minute, borrowed from strategy games, and it is the number people actually compete over. Anything above 120 means you are clicking hard enough that your wrist will tell you about it later.
GG
When the last block goes, the survivors stop hunting, drift to the middle and arrange themselves into two letters. That is the whole ending. No score screen, no retry prompt, just GG and a page with nothing left on it.
Why it is not in search any more
It shipped in 2012 as a live search feature and was retired later, which is why zerg rush removed and zerg rush easter egg removed still get typed in. The name comes from strategy games, where rushing means overwhelming someone before they can build anything.
The other game that ate a search page is google block breaker, though that one at least let you win. Spelling it is a minefield. Zarg rush, zerf rush, zerg ras, zury rush, zergrush, zerg berg. All the same game. Some people pair it with google mirror for a reversed round, which is harder than it sounds because your aim goes with it.
