There are too many enemies. At this rate...Master, the reinforcements are here. Call a servant quickly. The servant's unique skill will activate if you touch the skill slot. Annihilate the enemies with Eligos that has a powerful AoE attack skill. You've made use of the servant's power perfectly. You're amazing, master. The servant's skill os powerful, but time is required to use it again. Let's hunt the ghosts while waiting for the skill cool time. Let's go challenge the boss monster before more wraiths come swarming in. There are always guard monsters around the boss monster. If you spend too much energy on the guard monsters, you'll have a hard time fighting the boss. Wait until the boss monster comes close enough and then...Bam! if reinforcement didn't come in time, it would have been really dangerous.
We can't always rely on the servants. I've made a training manual, so trust and follow me. When you don't know what to do, press quests. You can grow souls that can be obtained by eliminating wraiths. I think what you need right now is strength! Can you point a gun with that arm?