This is obviously a very risky tactic as I will also have to be at low health, but you have to speculate to accumulate as they say

Class: Necromancer / Elementalist
Attributes: (cost)
Soul Reaping: 6 (21)
Blood Magic: 10 (61)
Air Magic: 4 (10)
Earth Magic: 12 (97)
Total attribute points used: 189/200
Skills:
1) Earth Attunement - (10,2,60) For 55 seconds, you are attuned to Earth. You gain 30% of the energy cost of the spell each time you use Earth Magic.
2) Armor of Earth - (10,1,15) For 30 seconds, you gain 53 armor, but move 21% slower than normal.
3) Blood Renewal - (5,1,10) Sacrifice 113 health. For 10 seconds, you gain health regeneration of 3. When Blood Renewal ends, you gain 113 health.
4) Touch of Agony - (5,1,5) Sacrifice 38 health. Target touched foe takes that much damage.
5) Dark Pact - (5,1,2) Sacrifice up to 32 health and do that amount of damage to target foe.
6) Chiron's Balance (elite) - (15,1,60) Health is equalized between you and target enemy. This is an elite skill.
7) Whirlwind - (10,1,20) All adjacent foes take 27 cold damage. Attacking foes struck by Whirlwind are knocked down.
8) Aftershock - (10,1,10) Nearby enemies are struck for 85 damage. Knocked down characters are struck for 56 additional damage.
I have never played a necro before and haven't played guild wars since they stopped giving out beta keys for free so I have no idea whether this would work.
Please crit, thanks.