Right, well starting negativly let me say that this is not a good film, if you are wanting good barbarian/warrior/fantasy type stuff go and get Lord of the Rings, or the much slated Krull. This is a B-movie, the specially effects are generally ropey, the plot is predictable and the acting is terrible, but......
If you accept all of this then the film itself is definetly watchable. The plot is simple, there are two warlords fighting over the only well in the settlement, they are evenly matched and it's the poor villages that get caught in the middle. Into town come the hero to help them, which he does by a bit of swordplay and some cuningness (not difficult when most of the people in the film are so dopey) playing the two warlords off against each other. This builds to a climactric fight scene at the end. Throw in a sorceress who does v little (eventually she makes a magic sword, which seems to have v little magic in it) and a slave trader and that's about it.
The plot is basically the same as a fistfull of dollars, which in itself I understand is a rip-off of a film called Yojimbo. Now OK it's been done before but the basic premise is sound and makes it a bit more interesting that the standard hack and slash.
It should be noted that this isn't really a family film, the sorceress spend the whole film topless, there is a dancing girl with 4 breasts (which actually look suprisingly realistic considering the rest of the special effects) and obviously quite a bit of violence. However I didn't find anything particularly offensive or uncomfortable, so as long as you don't mind semi-naked ladies and violence you should be fine (and if you do perhaps you shouldn't be looking at 80's fantasy flims with 18 certificates!)
The gist is this film is perhaps a little better than I was expecting, it is a low budget, 80's B-movie. If you accept this then it's a decent watch and the fact there is at least some kind of plot raises it above other similar films.