Jagged lines is a pattern constructed by Dean Hickerson in May 2005 that uses puffers to produce a line of bi-blocks that weaves back and forth in a complicated way.
In 2019, Dean Hickerson discovered that modifications to this pattern could create the variant patterns he dubbed mountain ranges. The size, slope, and composition of the "mountains" is highly variable and depends on the relative positions and phases of the rakes used to initiate the pattern.
Generation 10000 of this pattern, with the namesake "jagged line" of bi-blocks circled in green. The other lines are made up of gliders