Long feud with VenomFangX
The asshole Venomfangx has had a history with Thunderf00t, the most important moment is when VFX filed many DMCAs against Thunderf00t. Venom has appeared many times in Phil's videos, especially in the one where he got his ass kicked in the first part of "Why Do People Laugh At Creationists".
DawahFilms and Pz Myers
Dawah "The Moderate Muslim" Films, stalked Thunderf00t for over a year.
Dawah made idiotic claims, revealed Thunderf00t's name, threatened his life and revealed the university he (Phil Mason) worked at. Fortunately, the internet powers that be caught on to his cowardly methods and he stopped his activities before he did anything really stupid.