Alright, so I haven't counted, but I'm pretty sure that Maneater has been mentioned more than anyone else in the "Hardest Boss" thread… So I think we should offer different tips and strategies for beating him.
1. As listed on the wiki, you can kill the first one through the fog gate with a bow and a big supply of arrows. Pretty simple, but then you have to deal with the second one on your own. I personally never bother with this after figuring out my next 2 points due to the time it takes to kill from the fog gate, and I don't like to carry 200+ arrows depending on the playthrough.
2. For mages, one word: Firestorm. He is weak to fire, take advantage. A good spot to use it is at the flame in the middle, just wait for him to pounce, and cast immediately as he hs a long recovery time. ALTERNATIVELY, Fire Spray with maximum amounts of magic boosting equipment will deal admirable damage while keeping you mobile, just don't fall off a ledge.
3. For melee: Dragon weapons or Turpentine, Warding (or protection if you have only 1 slot), and HYPER ARMOR. Particularly, Dragon Miridan Hammers will annihilate a Maneater with ease. It it easy to target and dispatch his troublesom tail when his back is turned due to the hammer's range, and something I recently learned works AMAZINGLY WELL, the R2 attack can tank through his crazy knockdown and keep you from being sent off the edge, which is arguably the biggest threat from this beast. Always save some stamina for and emergency R2 in case he is about to do a pounce attack. Great/Crescent Axe might also be a good choice due to hyper armor, though I haven't really used them personally.
4. Though it deals damage at a slow rate, you can poison cloud him for at least some additional damage while he is flying around and you can't hit him.
5. If you are majorly hurt and need grass and have one or two maneaters on your ass, RUN to the other end of the bridge, as maneaters aren't the fastest runners and tend to fly in strange erratic patterns rather than going straight after you.