“OTCA Metapixel”, Life Wiki (cellular automata)⁠:

The OTCA metapixel (RLE) is a 2,048 × 2,048 period 35,328 unit cell that was constructed by Brice Due between the autumn of 2005 and the spring of 2006. It has many advantages over the previous-known unit cells such as the p5760 unit Life cell and deep cell, including the ability to emulate any Life-like cellular automaton and the fact that, when zoomed out, the ON and OFF cells are easy to distinguish (the ON version of the cell is shown to the right and the OFF version of the cell is shown below).

It is designed to run quickly under the Hashlife algorithm, and thus Golly is generally used to view and/or manipulate meta-patterns made up of OTCA metapixels (and some such patterns even come packaged with Golly).

Meta-metapixels: It is possible to use the OTCA metapixel to emulate itself, and emulate other patterns on the resulting meta-metapixel. Adam P. Goucher presented a meta-meta-blinker in December 2016, with a period of 2,496,135,168 (= 2 · 35,328²), noting that Golly can successfully run the entire period over the course of a day at a step size of 8⁵.