p76 pi-heptomino hassler is a small period-76oscillator found by David Raucci on April 11, 2021. It was originally found in the rotationally symmetric form of two pi heptominoes and two period-4 oscillators[1]; this form with a smaller period-4 oscillator has 82 cells. A monomer was found later the same day by James Pascua[2], which was then improved by Matthias Merzenich; this is the form with the minimum bounding box at 28×28[3]. On December 18, cvojan discovered that the oscillator could be stabilized by a traffic light-plus-eater 1catalyst; this form has the same bounding box but an even smaller population of 57 cells, and was formerly the smallest-known period-76 oscillator,[4] until the discovery of mold on 44P38 in 2022.
In its dual form, the bottom pi heptomino and associated heavyweight emulator can be moved one or two cells to the right, and the oscillator will still work.
On October 16, 2021, Raucci discovered that two of these oscillators could be used to create a p152 loaf hassler.[5]