Skill Two, “Ring of Earth,” on elementalist mainhand dagger in earth attunement says in the description that it blocks missiles. The Superior Rune of the Defender set grants one second of regeneration whenever an attack is blocked, and also grants a heal when an attack is blocked on a 30 second cooldown. However, these effects do not trigger when Ring of Earth blocks an attack. The only elementalist skill these Superior Rune of the Defender effects are triggered by is earth shield skill two, “Stone Sheath,” which is also described as having a block. In short, despite being described in the tooltip as a missile block, earth elementalist dagger skill 2 does not trigger the effects of the Superior Rune of the Defender set.