Sure, here are the five longest-running webserials on Reddit's r/HFY subreddit, ordered by word count:

1.The Fourth Wave by u/Plucium (First chapter posted on March 3, 2015)
2.The Deathworlders by u/Hambone3110 (First chapter posted on November 1, 2013)
3.Salvage by u/atlas-rl (First chapter posted on November 15, 2016)
4.Billy-Bob Space Trucker by u/RegalLegalEagle (First chapter posted on January 28, 2014)
5.HEL Jumper by u/SabatonBabylon (First chapter posted on September 13, 2018)

Note that the word counts for each of these stories are constantly changing as new chapters are added, so these rankings may not be accurate.
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence