Because as we showed today on not one but two occasions, humans no longer trade the casino formerly known as the 'stock market', we were glad to see that our old friend - the Whack-A-Mole algo - is back. As the following animated chart from Nanex shows, the algorithm is one which merely cycles in a broad, 10%+ sawtooth pattern blasting out empty quotes to feel the market in a test of other algos' responsiveness, and during a period of 6000 quote blasts, executes just under 20 actual trades. We will launch a catalog of all the various algos as we see them. After all, now that nobody else is left, it makes sense to at least make the acquaintance of all those robotic parasites that are the only entities left quote stuffing each other to death all the while, in true Knightian fashion, levitate the general market higher.
And as a special bonus, here is a reminder of what happened during the "BATS crash." From IPO to death in 750 milliseconds.