Nightblade Skill: Lifelink (Siphoning)
Links your health with that of your target. All healing and damage dealt to either you or the target is split evenly between the two. Lifelink can be cast on allies as well as enemies.
A fun siphoning skill if you think about it - if you're in a pvp fight you can cast it on an enemy, and then if you take a massive amount of damage from the opposition your enemy will take half of that damage (and you'll take half). If they attack you, they're essentially damaging themselves. If they heal themselves, they're healing you as well. It can also be cast on an ally in pve - so if you're a healer nightblade you could cast it on the tank in order to mitigate some extra damage, or if you're a tank nightblade and you lose aggro you could cast it on whoever in your group the enemy is targeting in order to absorb some of the damage away from them.
Nightblade Skill: Distortion Field (Shadow)
Distorts reality in the targetted area. Allies that enter the area gain invisibility. Hostiles that enter the area have their armor and spell resistance reduced. Hostile projectiles and spells targeted at allies within the area are nullified.
For the shadow line, we have this nifty ground-targeted aoe that buffs allies, debuffs enemies, and mitigates all spells and projectiles entering the area. Good pvp utility.
Nightblade Skill: Deathclock (Assassination)
Deals damage over time to the target, and increases your critical strike chance, weapon damage, and spell damage when attacking the target, for 30 seconds. If the target dies before the effect ends, you gain 100% of your maximum life, magicka, and stamina. If the target is still alive when the effect ends, you die.
High risk, high reward, the assassin's playstyle - yes?
Templar Skill: Phalanx (Aedric Spear)
Summons four spear-wielding aedric spirits to fight by your side for 10 seconds. The spirits will mimic your aedric spear abilities.
By mimic, I mean that when you cast biting jabs, they'll all cast biting jabs (dealing less damage, of course) - when you cast blazing spear, they cast blazing spear, so on and so forth. Your own little army of spear wielding dopplegangers.
Templar Skill: Divine Judgement (Dawn's Wrath)
Creates a blazing ball of light at the targeted location that pulls nearby enemies towards it, dealing damage over time. Deals additional damage to undead and daedric enemies.
Going on the celestial theme of the dawn's wrath skills, this is basically like a black hole (but all holy and stuff) that sucks your enemies in while damaging them.
Templar Skill: Sacrifice
Your health bar is traded with the lowest health party member.
Basically a health bar swap for those oh crap healer situations. Say you've got 1500 health, and a nearby ally only has 500 health and is about to die - you hit sacrifice, and now you've got 500 health and the ally has 1500 health. Of course, this ability could get you killed... hence the name.