The options menu found at the top right of interface and is symbolised by a gear icon.
See here for account linking.
Sound and music are self explanatory and so is graphics.
The blood option will squirt blood on screen when a champion is killed.
Show helmets option when active will show helmets. when off then it will look like champions aren't wearing helmets. They are still though it won't reduce the stats effect from helmets.
Force PvP will make single matches similar to how arena is. That is you wait 10 seconds before a force AI fight button will pop up. When off you will automaticly be paired with the AI. The force pvp will allow you sit and wait until an opponent is found.
Inner Demon will hide demon mutuations showing the gear or cosmetics underneath. If this is off then cosmetics and gear won't be shown.
Hide Ascension works similar to inner demon just will hide ascension showing cosmetics.
Hide Weather Turns off weather effects during events like snow during xmas. Helps to reduce lag.
Hide Announcements Will stop the chat showing unread message counts of non admin announcements. This means the messages from gaining mutations and legendary or unreal weapons. They will show in chat but not be marked as unread.
Low Statsbars Will lover the stat bar in battles helpful for seeing stat bar in battles of large enemies.
Quick sell options
When vip 5 is reached all loots can be auto sold or auto salvaged when activated. Light up the boxes of the rarity to Auto sell. Both auto sell and salvage can't be on same time though.