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This person creates low-quality "articles" en masse on small wikis and then reports on Wikimedia News (previously, when it was still used, also on template/temp) that the project surpassed a certain milestone (e.g. 1000 articles) thanks to his nonsense. He also edits on English wikis sometimes (usually vandalism).

The articles are easily recognizable: Either they are meaningless articles about numbers ("1/2/3/4/5/.../265 is a number."), about letters ("A/B/C/D/E is the nth letter of the alphabet."), about "American pop culture" (Mario Kart, Disney, "Baskin-Robbins", [1]). In the past he also copied articles from enwiki, sometimes applying Google Translate, sometimes just copying.

Still active as of November 2018.

see also: en:Wikipedia:Sockpuppet investigations/Mason Decker/Archive