I actually think it may be the new version of Hunter Gammas, which were these things:I first though it was Grave digger too, but it's a bit small for that and clearly has legs and a frog-like tail (the other Hunters in REmake 3 also have a tail). Hunter Gammas only appeared twice I think in the original RE3 and if it is them they've been GREATLY redesigned, but I like their new look.