Artifacts and rings don’t have a tier. This only applies to weapons and armor.

Suppose you’re wearing cloth armour and using studded gloves (both tier 1). With this talent at level 3 you’ll get the maximum benefit.

Now suppose you equip a ring of force. Note that equipping a ring of force while using a weapon does not immediately count as “attacking with a ring of force.”

Now notice that the ring of force has a Duelist ability called brawler’s stance. When you activate it (takes no time and costs nothing) you will switch to attacking with your ring of force instead of your gloves. Now if you kill an enemy you’ll only get the benefit of your armour, not your gloves.

But here’s the thing! You can toggle brawler’s stance on and off any time at no cost and no time. So you can use it to soften up an enemy with your ring of force and then turn it off and finish them using a flurry of blows or a regular punch from the gloves. As long as the enemy dies with brawler’s stance toggled off you’ll get the benefit of your gloves for extra energy!