Until 6 months ago, we had 3 chilled out, easy going cats. We decided that we had room in our house and our hearts for one more, so we got a rescue cat.
He was ever so friendly and chilled out until we introduced (very gradually) our other cats to him. Ever since then he's been aggressive and vicious to everyone - us (including 2 DCs), and the other cats.
It's very rare that we can approach him for a stroke without him scratching or biting us unless we have food, or it's the middle of the night and he's all sleepy. He constantly picks fights with our other cats - one of them in particular he absolutely terrorises - chases her all the time.
All our cats are neutered (devil-cat included), we've tried feliway diffusers, there's plenty of feeding bowls, we have a cat flap and a large safe garden, and 3 bedrooms and 3 reception rooms that the cats all have access to, so there really shouldn't be a territory issue. Not only is he terrorising our cats, he's terrorising other cats in the area.
However, when the other cats aren't around, he's much friendlier. He pops around to our neighbours and will let them stroke him, but again, not if there's another cat in sight.
To get to the point - should we re-home him? I feel we've given him enough of a chance to settle in and grow up, he's making our cats lives a misery, and he can't be that happy himself if he's affectionate when the other cats aren't around. Surely he'd be happier in a loving home with no other cats?
I hate to give up a cat for adoption (and in many ways I'd be happy to do a swap), but I just don't feel it's working.