TMNT vs Hellboy

Round 1: Mirage

Round 2: IDW

In character

Winner by KO, incapacitation or death

Random encounter

Standard gear and abilities

Fight takes place at an unpopulated city setting at night

Who'd win? For what reasons?

Hellboy has superhuman durability and a healing factor nearly on par with Wolverine.

It will take him a long time to hit them, due to their superior speed and agility, but there's really nothing they can do to seriously hurt him.

Hellboy should win.

Hellboy kills them then sends then to hell

Hellboy vs. TMNT's 1980's version of Metalhead would be a neat encounter.