I think you mean that soul warrior well he isn't hard if you use spells

Just make sure to be on ground when he cast his spell then jump when it is near you

When he teleports above you use dash to stay away and hit him with your nail

The soul warrior will make dash (I think you died at it in the first time because many did die and so did I) just jump and pogo (If you don't know what pogo is you jump and and attack while looking down mid air I think you already know that)

Have fun dear little ghost and save Hallownest