Wiki Q&A

The supplied context does not identify a "best" Mastery Chain link for a "holy tank dexxer" build, and it does not contain any chunk that defines or evaluates a "holy tank dexxer" archetype. So I cannot give a supported recommendation for that specific build.

What the context does support about Mastery Chain links in general:

• Mastery Chain links provide PvM bonuses, and players can add links once they have gained the required XP to unlock a link slot [1].
• Players may install up to 10 Chain Links of the same bonus effect into a single Mastery Chain, increased up to 15 with a redline upgrade; the only exception is "Special / Rare Drop Chances," which allows 20 links [1][2].
• Some example link effects listed include Damage Resistance, Defense, Effective Magic Resist Skill, Effective Parrying Skill, Healing Received, and Effective Skill on Chests [1].
• By default, PvM bonuses that only affect monsters remain in place while a player is flagged in PvP; examples of links that remain in effect while PvP flagged include Damage resistance and Defense [1].
• Effects that by their nature have an inherent chance to affect PvP will always be disabled when a player is flagged in PvP [1].

Requested details not present in the supplied context:

• No definition or stat profile for a "holy tank dexxer."
• No ranking, tier list, or "best link" recommendation for any dexxer, tank, or holy-themed build.
• No chunk connecting specific links (such as Damage Resistance or Defense) to a "holy tank dexxer" build.