Finn is a fictional pagan warlock eco-terrorist created by Pat Mills. He first appeared in British fortnightly anthology comic Crisis in 1989 in the strip Third World War and later moved to an eponymous series in 2000 AD after Crisis was cancelled in 1991.

The character was popular but the series ended in 1996. According to David Bishop the reason the character was suspended was due to concerns that he was in danger of duplicating the appeal of Mills's Sláine. Mills has speculated that part of the reason was because some readers were complaining in the letters page about Finn "being a sinister witch and saying his authentic pagan practices were a bad example to readers".

Finn is the alias of Paul. In Third World War it is established that Paul was once a soldier in the British Army stationed in Northern Ireland, but he deserted to become Finn, an eco-terrorist fighting to save the planet from multi-national corporations.

Third World War starts as a relatively down-to-earth story set in 2000, with very little in the way of fantasy or science fiction but that changes as Finn becomes more prominent.

In the eponymous strip in 2000 AD it emerges that the leaders of the corporations are in fact a secret society of powerful aliens called Newts. In this strip Finn is a Cornish mini-cab driver by day, and a white witch fighting the aliens by night. He uses military equipment alongside magical items such as the Hand of Glory.

He has appeared first as a supporting character in the series Third World War in the comics magazine Crisis then in the eponymous strip in 2000 AD:

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