Almost knightship is a partialspaceship discovered by Eugene Langvagen on March 23, 2004 using afind.[1] It would have been an elementary knightship if two cells at the back end were not incorrect after the 6th generation, which provided evidence that small elementary knightships may exist within a considerably small bounding box. The original search also found a slightly longer incomplete result with more incorrect cells.
Several more small almost knightships were found by Tomas Rokicki in February 2018, using a SAT solver,[2] of velocities (2,1)c/6 and (2,1)c/7. Further searching by Adam P. Goucher based on these partials led to the finding of a true elementary knightship, Sir Robin. Similarly, another almost knightship by Dylan Chen[3] was completed to give Sprayer. However, as of March 2025, none of life's knightships use the front end of the original almost knightship.
A further (2,1)c/7 almost knightship where 4 extra cells are produced in the formation of a spark was found by Goucher on December 12, 2020.[4] As of March 2025, though, no period-7 knightships have been found in regular Life.
