10. Nashandra - Dark Souls 2
When most players reach Nashandra, the encounter will be made more challenging by the fact that they'll have just come out of a gruelling battle with the Throne Watcher and Throne Defender. This is the first of many problems with Nashandra - she has to rely on her lackies to soften you up. When you finally fight the Grim Reaper's wife, you can see why she needed some backup.
Nashandra is slow and predictable, swinging her scythe like a sclerotic farmer, and firing an easily-avoidable laser beam. In a move that you'd expect from a game's first boss rather than its last one, the hapless old wench also tends to get her scythe stuck in the ground.
As you look at her - all decrepit, bony and struggling to wrench her scythe out of the ground - you almost feel like you should help her like you would any old lady carrying her groceries. The insufficiency of the Nashandra fight was not lost on From Software, who in an unprecedented move, patched the game and - along with many other changes - thankfully added in another boss fight after just to keep gamers on their toes.