Runescape is described as 'The most popular free MMO in the world, by Jagex Games Studio. Complete quests and win enormous treasures in a 3D world full of magic and monsters- all while never leaving your internet browser' and is a role-playing game in the games category. There are more than 50 games similar to Runescape for a variety of platforms, including Windows, Linux, Mac, Android and Web-based apps. The best Runescape alternative is The Elder Scrolls. It's not free, so if you're looking for a free alternative, you could try The Lord of the Rings Online or The Mana World. Other Runescape like games are World of Warcraft, Guild Wars, EverQuest and Sacred.
Both games focus on tradeskills and other activities, rather than just hunting monsters and doing quests. BUT you can indeed hunt monsters if you so wish; With some absolutely spectacular fighting.