General outline of party structure and skills equipped by each
Team:
earth tank
R/Rt
N/Me
nuke ele
nuke ele
nuke ele
bonder
healer

1 earth tank
core skills:
 
possible additional skills depending on primary/secondary professions:


1 R/Rt
 shortens battles by a huge margin,  optional.

Core PvE only Barrage 1 5 Elite Bow Attack. All your Preparations are removed. Shoot arrows at up to 6 foes adjacent to your target. These arrows strike for +1..16 damage if they hit. (Attrib: Marksmanship) Prophecies PvE only Frozen Soil 30 5 10 Nature Ritual. Create a level 1..10 Spirit. Non-Spirit creatures within its range cannot resurrect dead allies. This Spirit dies after 30..90 seconds. (Attrib: Wilderness Survival) Factions PvE only Splinter Weapon 5 1 5 Weapon Spell. For 20 seconds, target ally has a Splinter Weapon. Target ally's next 1..5 attacks deal 5..50 damage to all adjacent foes. (Attrib: Channeling Magic) Nightfall PvE only Gaze of Fury 20 2 10 Binding Ritual. Destroy target Spirit and create a level 1..10 Spirit of Fury. This Spirit's attacks deal 5..20 damage. This Spirit dies after 30..60 seconds. (Attrib: Channeling Magic) Core PvE only Savage Shot 5 ½ 10 Bow Attack. If Savage Shot hits, your target's action is interrupted. If that action was a Spell, you strike for +13..28 damage. (Attrib: Marksmanship) Core PvE only Distracting Shot 10 ½ 5 Bow Attack. If Distracting Shot hits, it interrupts target foe's action but deals only 1..16 damage. If the interrupted action was a skill, that skill is disabled for an additional 20 seconds. (Attrib: Expertise) Factions PvE only Flesh of My Flesh 4 5 Spell. Lose half your Health. Resurrect target ally with your current Health and 5..20% Energy. (Attrib: Restoration Magic)

1 N/x (N/Me)
Optional  to replace  for Duncan fight,  a must for Duncan fight

 

3 E/x (E/A)
For the Duncan fight, one ele must have  equipped to move out the spawned damage spirits




1 bonder (Mo/E)


1 healer (Mo/E)


Comments on the above build:
Remember that the above is just a general outline and guide for what people should consider bringing.
The tank is usually E/Me or W/E.

Strategy:
At least for the first three parts of Slaver's Exile, anything goes. I can't say the same for Forgewight and Duncan.

Move out into the zone, kill the first group, run the rest to Slaver's Exile.

Bond the tank.

Tank goes out, enchant up, gets aggro.
Pull as far as possible.
Best to bodyblock with one side to a wall.
Snare and call out Grasping Earth to signal start of ele nukage.
Depending on enemy mob size and composition, start with 3 Meteor Showers or 3 Savannah Heats.

Ranger must watch for and eliminate spawns of spirits, especially the Disenchantment.
Maintain Frozen Soil at all times, in a safe location but within effective range to prevent Stone Summits from using resurrect skills.

Duncan fight:
Pop and clear all the touch necros around Duncan.
Tank runs up to Duncan, dies. Leave the tank there.
Meantime, the E/A with Swap goes out and move damage spirits near the bottom of the stairs(Disenchant, Shadowsong, Pain) away from party.

Necro goes in at the corner next to the stairs where it is protected from spirit attacks and Duncan's wanding.
Monks maintain heal and protection on the necro.
Necro spams Signet of Sorrow and any damage spells on Duncan.

The end.

When Tilan(healer), me(nuker), Vane(bonder), Selina(tank), and Skye(nuker) did Forgewight/Duncan...
We replaced the ranger, added a 4th nuker, and split the Frozen Soil, Symbiosis, and Gaze of Fury/Flesh of My Flesh among the hero nukers and SS necro hero into something like this:

Nightfall PvE only Swap 10 ¼ 5 Spell. You and target summoned creature Shadow Step to each other's location. Nightfall PvE only Savannah Heat 25 2 5 Elite Spell. You create Savannah Heat at target foe's location. For 5 seconds, all nearby foes take 5..20 damage each second and an additional 5..20 damage for each second this Spell has been in effect. (Attrib: Fire Magic) Core PvE only Glyph of Elemental Power 5 1 5 Glyph. For 25 seconds, your elemental attributes are boosted by 2 for your next 10 Spells. Prophecies PvE only Searing Heat 30 2 15 Spell. Cause Searing Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Searing Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Eye of the North PvE only "Finish Him!" 15 10 Shout. If target foe has less than 50% Health, that foe takes 20..80 damage and suffers from Cracked Armor and a Deep Wound for 5..20 seconds. (Attrib: Norn rank) Prophecies PvE only Meteor Shower 60 5 25 Spell. Create a Meteor Shower at target foe's location. For 9 seconds, foes adjacent to that location are struck for 7..112 fire damage and knocked down every 3 seconds. This Spell causes Exhaustion. (Attrib: Fire Magic) Eye of the North PvE only Air of Superiority 20 5 Skill. For 10..30 seconds you gain a random Asura benefit every time you earn experience from killing an enemy. (Attrib: Asura rank) Core PvE only Fire Attunement 45 2 10 Enchantment Spell. For 36..60 seconds, you are attuned to Fire. You gain 1 Energy plus 30% of the base Energy cost of the Skill each time you use Fire Magic. (Attrib: Fire Magic)

Maaya

Prophecies PvE only Frozen Soil 30 5 10 Nature Ritual. Create a level 1..10 Spirit. Non-Spirit creatures within its range cannot resurrect dead allies. This Spirit dies after 30..90 seconds. (Attrib: Wilderness Survival) Nightfall PvE only Savannah Heat 25 2 5 Elite Spell. You create Savannah Heat at target foe's location. For 5 seconds, all nearby foes take 5..20 damage each second and an additional 5..20 damage for each second this Spell has been in effect. (Attrib: Fire Magic) Core PvE only Glyph of Lesser Energy 30 1 5 Glyph. For the next 15 seconds, your next 2 Spells cost 10..18 less Energy to cast. (Attrib: Energy Storage) Prophecies PvE only Searing Heat 30 2 15 Spell. Cause Searing Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Searing Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Prophecies PvE only Mark of Rodgort 15 1 15 Hex Spell. Target foe and all nearby foes are Hexed with Mark of Rodgort. For 10..35 seconds, whenever each foe is struck for fire damage, that foe is set on fire for 1..4 seconds. (Attrib: Fire Magic) Prophecies PvE only Meteor Shower 60 5 25 Spell. Create a Meteor Shower at target foe's location. For 9 seconds, foes adjacent to that location are struck for 7..112 fire damage and knocked down every 3 seconds. This Spell causes Exhaustion. (Attrib: Fire Magic) Factions PvE only Teinai's Heat 30 2 15 Spell. Create Teinai's Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Teinai's Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Core PvE only Fire Attunement 45 2 10 Enchantment Spell. For 36..60 seconds, you are attuned to Fire. You gain 1 Energy plus 30% of the base Energy cost of the Skill each time you use Fire Magic. (Attrib: Fire Magic)

Maaya's Zhed

Prophecies PvE only Spiteful Spirit 10 2 15 Elite Hex Spell. For 8..20 seconds, whenever target foe attacks or uses a skill, Spiteful Spirit deals 5..35 shadow damage to that foe and all adjacent allies of that foe. (Attrib: Curses) Prophecies PvE only Insidious Parasite 12 1 15 Hex Spell. For 5..15 seconds, whenever target foe hits with an attack, you steal up to 15..45 Health from that foe. (Attrib: Curses) Core PvE only Enfeebling Blood 5 2 10 Spell. Sacrifice 10% maximum Health. Target foe and all nearby foes suffer from Weakness for 5..20 seconds. (Attrib: Curses) Nightfall PvE only Signet of Lost Souls 8 ¼ Signet. If target foe is below 50% Health, you gain 10..100 Health and 1..10 Energy. (Attrib: Soul Reaping) Nightfall PvE only Signet of Sorrow 30 1 Signet. Target foe takes 15..75 damage. If target foe is near a corpse or has a dead pet, this Skill recharges instantly. (Attrib: Soul Reaping) Prophecies PvE only Blood Ritual 2 2 10 Enchantment Spell. Sacrifice 17% maximum Health. For 8..14 seconds, target touched ally gains +3 Energy regeneration. Blood Ritual cannot be used on the caster. (Attrib: Blood Magic) Nightfall PvE only Gaze of Fury 20 2 10 Binding Ritual. Destroy target Spirit and create a level 1..10 Spirit of Fury. This Spirit's attacks deal 5..20 damage. This Spirit dies after 30..60 seconds. (Attrib: Channeling Magic) Factions PvE only Flesh of My Flesh 4 5 Spell. Lose half your Health. Resurrect target ally with your current Health and 5..20% Energy. (Attrib: Restoration Magic)

Master of Whispers

(replace signet of lost souls with reckless haste for Forgewight)

Core PvE only Arcane Echo 20 2 15 Enchantment Spell. If you cast a Spell in the next 20 seconds, Arcane Echo is replaced with that Spell for 20 seconds. Arcane Echo ends prematurely if you use a non-Spell skill. Nightfall PvE only Savannah Heat 25 2 5 Elite Spell. You create Savannah Heat at target foe's location. For 5 seconds, all nearby foes take 5..20 damage each second and an additional 5..20 damage for each second this Spell has been in effect. (Attrib: Fire Magic) Core PvE only Glyph of Elemental Power 5 1 5 Glyph. For 25 seconds, your elemental attributes are boosted by 2 for your next 10 Spells. Prophecies PvE only Searing Heat 30 2 15 Spell. Cause Searing Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Searing Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Eye of the North PvE only "Finish Him!" 15 10 Shout. If target foe has less than 50% Health, that foe takes 20..80 damage and suffers from Cracked Armor and a Deep Wound for 5..20 seconds. (Attrib: Norn rank) Prophecies PvE only Meteor Shower 60 5 25 Spell. Create a Meteor Shower at target foe's location. For 9 seconds, foes adjacent to that location are struck for 7..112 fire damage and knocked down every 3 seconds. This Spell causes Exhaustion. (Attrib: Fire Magic) Eye of the North PvE only Air of Superiority 20 5 Skill. For 10..30 seconds you gain a random Asura benefit every time you earn experience from killing an enemy. (Attrib: Asura rank) Core PvE only Fire Attunement 45 2 10 Enchantment Spell. For 36..60 seconds, you are attuned to Fire. You gain 1 Energy plus 30% of the base Energy cost of the Skill each time you use Fire Magic. (Attrib: Fire Magic)

Skye

Prophecies PvE only Symbiosis 60 5 5 Nature Ritual. Create a level 1..10 Spirit. For each Enchantment on a non-Spirit creature within range, that creature has +27..150 maximum Health. This Spirit dies after 30..150 seconds. (Attrib: Beast Mastery) Nightfall PvE only Savannah Heat 25 2 5 Elite Spell. You create Savannah Heat at target foe's location. For 5 seconds, all nearby foes take 5..20 damage each second and an additional 5..20 damage for each second this Spell has been in effect. (Attrib: Fire Magic) Core PvE only Glyph of Lesser Energy 30 1 5 Glyph. For the next 15 seconds, your next 2 Spells cost 10..18 less Energy to cast. (Attrib: Energy Storage) Prophecies PvE only Searing Heat 30 2 15 Spell. Cause Searing Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Searing Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Prophecies PvE only Mark of Rodgort 15 1 15 Hex Spell. Target foe and all nearby foes are Hexed with Mark of Rodgort. For 10..35 seconds, whenever each foe is struck for fire damage, that foe is set on fire for 1..4 seconds. (Attrib: Fire Magic) Prophecies PvE only Meteor Shower 60 5 25 Spell. Create a Meteor Shower at target foe's location. For 9 seconds, foes adjacent to that location are struck for 7..112 fire damage and knocked down every 3 seconds. This Spell causes Exhaustion. (Attrib: Fire Magic) Factions PvE only Teinai's Heat 30 2 15 Spell. Create Teinai's Heat at target foe's location. For 5 seconds, foes near this location are struck for 10..40 fire damage each second. When Teinai's Heat ends, foes in the area of effect are set on fire for 3 seconds. (Attrib: Fire Magic) Core PvE only Fire Attunement 45 2 10 Enchantment Spell. For 36..60 seconds, you are attuned to Fire. You gain 1 Energy plus 30% of the base Energy cost of the Skill each time you use Fire Magic. (Attrib: Fire Magic)

Skye's Zhed

The rest being along the lines of:

Nightfall PvE only Signet of Stamina 20 ¼ Signet. You have +50..300 maximum Health. This Signet ends if you successfully hit with an attack. (Attrib: Strength) Prophecies PvE only Glyph of Concentration 10 1 5 Glyph. For 15 seconds, your next two Spells cannot be interrupted and ignore the effects of being Dazed. Nightfall PvE only Stoneflesh Aura 15 2 10 Enchantment Spell. For 5..15 seconds, damage you receive is reduced by 1..31, and you are immune to critical attacks. (Attrib: Earth Magic) Core PvE only Armor of Earth 15 ¾ 10 Enchantment Spell. For 30 seconds, you gain 24..60 armor, but move 50..14% slower. (Attrib: Earth Magic) Prophecies PvE only Grasping Earth 12 ¾ 5 Hex Spell. For 8..20 seconds, all nearby foes move 50% slower. (Attrib: Earth Magic) Core PvE only Ward Against Foes 20 1 15 Ward Spell. You create a Ward Against Foes at your current location. For 8..20 seconds, non-Spirit foes in this area move 50% slower. (Attrib: Earth Magic) Core PvE only Earth Attunement 45 2 10 Enchantment Spell. For 36..60 seconds, you are attuned to Earth. You gain 1 Energy plus 30% of the base Energy cost of the Skill each time you use Earth Magic. (Attrib: Earth Magic) Core PvE only Obsidian Flesh 30 1 10 Elite Enchantment Spell. For 8..20 seconds, you gain +20 armor and cannot be the target of enemy Spells, but move 50% slower. (Attrib: Earth Magic)

Selina

Prophecies PvE only Balthazar's Spirit 2 10 -1 Enchantment Spell. While you maintain this Enchantment, target ally gains adrenaline and Energy after taking damage. (The amount of adrenaline gained increases depending on your rank in Smiting Prayers.) (Attrib: Smiting Prayers) Target ally gets healed for 38 Health. Core PvE only Life Bond 2 10 -1 Enchantment Spell. While you maintain this Enchantment, whenever target other ally takes damage from an attack, half the damage is redirected to you. The damage you receive this way is reduced by 3..30. (Attrib: Protection Prayers) Target ally gets healed for 38 Health. Core PvE only Protective Spirit 5 ¼ 10 Enchantment Spell. For 5..23 seconds, target ally cannot lose more than 10% max Health due to damage from a single attack or Spell. (Attrib: Protection Prayers) Target ally gets healed for 38 Health. Core PvE only Glyph of Lesser Energy 30 1 5 Glyph. For the next 15 seconds, your next 2 Spells cost 10..18 less Energy to cast. (Attrib: Energy Storage) Nightfall PvE only Seed of Life 25 ¼ 5 Enchantment Spell. For 1..5 seconds, whenever target other ally takes damage, all party members are healed for 2 Health for each rank in Divine Favor. (Attrib: Sunspear rank) You get healed for 38 Health. Prophecies PvE only Restore Condition 2 ¾ 5 Elite Spell. Remove all Conditions (Poison, Disease, Blindness, Dazed, Bleeding, Crippled, Burning, Weakness, and Deep Wound) from target other ally. For each Condition removed, that ally is healed for 10..70 Health. (Attrib: Protection Prayers) Target ally gets healed for 38 Health. Core PvE only Signet of Devotion 5 2 Signet. Heal target ally for 14..100 Health. (Attrib: Divine Favor) Core PvE only Rebirth 5 10 Spell. Resurrect target party member. Target party member is returned to life with 25% Health and zero Energy, and is teleported to your current location. All of target's skills are disabled for 10..3 seconds. This Spell consumes all of your remaining Energy. (Attrib: Protection Prayers)

Vane

Nightfall PvE only Healer's Boon 10 ¼ 5 -1 Elite Enchantment Spell. While you maintain this Enchantment, your next 10..30 Healing Prayers Spells cast 50% faster and heal for 50% more Health. (Attrib: Divine Favor) You get healed for 38 Health. Core PvE only Glyph of Lesser Energy 30 1 5 Glyph. For the next 15 seconds, your next 2 Spells cost 10..18 less Energy to cast. (Attrib: Energy Storage) Core PvE only Heal Party 2 2 15 Spell. Heal entire party for 16..80 Health. (Attrib: Healing Prayers) You get healed for 38 Health. Nightfall PvE only Seed of Life 25 ¼ 5 Enchantment Spell. For 1..5 seconds, whenever target other ally takes damage, all party members are healed for 2 Health for each rank in Divine Favor. (Attrib: Sunspear rank) You get healed for 38 Health. Prophecies PvE only Heal Other 3 ¾ 10 Spell. Heal target other ally for 35..180 (+38) Health. (Attrib: Healing Prayers) Eye of the North PvE only Cure Hex 12 1 5 Spell. Remove one Hex from target ally. If a Hex was removed, that ally is healed for 30..120 Health. (Attrib: Healing Prayers) Target ally gets healed for 38 Health. Prophecies PvE only Dwayna's Kiss 3 1 5 Spell. Heal target other ally for 15..60 (+38) Health and an additional 10..35 Health for each Enchantment or Hex on that ally. (Attrib: Healing Prayers) Core PvE only Rebirth 5 10 Spell. Resurrect target party member. Target party member is returned to life with 25% Health and zero Energy, and is teleported to your current location. All of target's skills are disabled for 10..3 seconds. This Spell consumes all of your remaining Energy. (Attrib: Protection Prayers)

Tilan

I had Frozen Soil, Gaze of Fury, Blood Ritual and Flesh of My Flesh disabled during most of the fights, manually activating them when needed. (You don't want the necro immediately getting rid of Symbiosis or try to BR the tank during the battle/aggroing, or Zhed putting down Frozen Soil at the wrong places) Enfeebling Blood was also disabled during the Duncan fight.

I tended to stay 1 1/2 aggro bubble away from where the tank is, then a running start to cast Meteor Shower when Grasping Earth was called and at the same time manually force Zhed to lay down Frozen Soil. Follow up Meteor Shower with Savannah Heat, then Searing Heat.
Killed off stragglers with "Finish Him!" and other nuke spells as they recharge.

The necro hero being the SoS Duncan-killer wasn't a big problem, just had trouble finding the sweet spot where he doesn't move around.