Castrum Fluminis is way too difficult

[Pepsi_Plunge]

IThe instant death mechanic from the half moons is very unforgiving and is an extreme steep curve in difficulty compared to the other fights you've done.

Do you mean the debuff which tells you on which side (light or darkness) you need to stay? How is this extremly difficult? Just watch the symbol and change sides according to the buff. You also have time until it slowly counts up to 5 before you die and it resets each time you step on the right side.

Seriously, just keep an eye on the symbol and stay near the line so you can switch sides as often as necessary. Best to do it as soon as the number reachs 2, or so. Don't wait until it's 4.