Gear
Tl;dr - 5 pc alkosh, 5 pc ebon, 1 pc mighty chudan, 1 pc pirate skeleton, 2 pc swarm mother in some situations, 5 pc powerful assault in some situations

Alkosh and ebon are by and large the best tank sets in the game. You're almost guaranteed synergies in a group, so its a massive boost to group dps. Ebon just adds that extra little cushion to the group to help them survive. For dungeons not including vet cradle of shadows and ruins of mazzatun, you can switch out ebon for powerful assault and absorb magic on your back bar to echoeing vigor. This will add even more dps in exchange for some survivability, but there is such a thing as overtanking and for most content as a max cp character you can be a tank in full medium with a shield with the right cp allocation. As you're not wearing any sets that give resistance buffs,1 pc chudan and 1 pc skeleton will get you closer to that resistance cap. If you're not switching out anything for powerful assault you can sub in swarm mother to have auto-chains and pull mobs into the aoe's of your group. Unlike some builds, it is essential you have the right sets in the right gear piece. You need jewelry and sword and board alkosh, that way you're full heavy armor and reach that resistance cap.

Rotation
This build will give you self and group healing, does solid aoe damage, major and minor resistance buffs, self resource regen, the possibility of absorbing projectiles for health, 8% reduced block cost and 8% increase in blocked damage, major dodge chance, has long and short range taunts, debuffs enemy resistances a ton, and debuffs enemy damage. Start off with refreshing path, siphoning attack, puncture, swallow soul, bar swap, mirage, sap essence, heroic slash, bar swap, spam swallow soul until siphoning attacks wears off (you can tell cause it makes whoosh noise), repeat. In aoe trash mob situations apply your buffs but instead of spamming swallow soul spam sap essence. You will be permablocking this whole time, your stamina regen comes from swallow soul procing siphoning attacks. If you do need resources, light attack when an opening presents itself.

Stats
You want 30k health and no less than 15k stamina unbuffed, the rest goes to magicka.