Useful combos?
These are some simple ones that I’m involved with all of the time on my Thief and Warrior.
Ranged attacks + Darkness Field = free Lifedrain for the Ranged attackers
Ranged attacks + Smoke Field = lots of Blind stacks on the mobs
Blast attacks + Water Field = AoE heals
Blast attacks + Fire Field = AoE Might stacks x3 (per Blast)
For more general information on combos and the MANY possibilities, see the link from the GW2 Wiki below.
Particularly effective ones in small groups are putting down fire fields + blast finisher for 3 stacks of area might. Another really awesome one is a Light Field + Blast finisher for area retaliation. Shooting projectiles through any kind of poison or fire field is useful for added conditions, and personally I like making a smoke field for projectiles as the constant blind is very useful against bosses. A mesmer putting down whatever the field type their Time Warp Elite is and firing through it is nice as well as it puts on confusion (No idea what kind of field that one is). Putting fields down near a dual axe warrior or an axe off-hand ranger are nice as well because their whirl attacks put off flaming and such projectiles from their spin. One of my personal favorites is using frozen ground on my Ele and having someone fire through it or use a blast finisher. First one chills enemies it hits, and since it stacks duration someone firing rapidly through it gives really awesome chill which is incredibly useful against just about anything, and the blast finisher gives area frost armor which also chills.
There are still plenty more combos out there, but these are ones I actually use or come across a lot. As an elementalist I can put a ridiculous amount of combo fields and “bases” down for people, and my party members always make excellent use of them in dungeons. Sometimes I also carry around Arcane Blast as a blast finisher, and I use my rock projectiles from my scepter auto-attack through any field I can, even though it is only a 20% chance it is still useful.
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