The two combat addons is necessary in The Elder Scrolls Online- Greymind Quick Slot Bar and Kill Counter. They are simple but useful.

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Greymind Quick Slot Bar 

The biggest disadvantage of the basic interface of Elder Scrolls online is that we don't fast switch equipment and seeting. This addon can allow us quickly switch potions and weapons. It is high custom. But for me, I like the six item bars, which make me operation more convenient.

alt="Important ESO Combat Addons: Greymind Quick Slot Bar and Kill Counter" 

Kill Counter

alt="Important ESO Combat Addons: Greymind Quick Slot Bar and Kill Counter" 

To only clear data lets you know whether your character is improved. Thus  Kill Counter is a significant addon in the TESO world. Most importantly, you need to note the  Kills / Death Ratio (K / D), Killing Blows (KB), AP Gain.

Kills / Death Ratio- In a good case, Kills / Death Ratio is 10:1. For solo PVP, it often 6:1. You can try your best to improve K/D.

Killing Blows- It depends on your location. To note the KB date, you can get more killed enemies.

AP Gain- It is the best data to record your battlefield contributions. A wonderful AP list can have others worship you