The aim of this guide is to help you get past the final boss encounter in Hellblade: Senua's Sacrifice.
Other Hellblade Guides:
This guide technically contains spoilers, so I would only recommend reading it if you have tried your luck against the final boss and hit a wall.
The final boss battle contains of three phases. Each phase will be fought on a different platform. These platforms are connected by bridges. These bridges will get shattered by the final boss. Once you defeat the enemies on your current platform, simply walking towards the shattered bridge will cause it to reassemble itself, allowing you advance closer to the final boss.
The first phase is straight forward. Move towards the final boss and kill the minions you encounter along the way using already familiar techniques.
The second phase will require you to fight shadow versions of the first three bosses. This phase will evolve from fighting one shadow boss at a time to fighting two of them at a time (in various combinations). Be mindful of your surroundings, use the same strategies you used to defeat these bosses in the first place and you should be fine.
The third and final phase is where I got stuck for a while (hence this guide). The final boss is located in the middle of the platform and you are surrounded by minions. You cannot damage the final boss and minions on this platform spawn in endless waves. Let the minions defeat you in order to proceed.