All top solo IA are Nightblade. Why?

ImmortalCX

What is it about the nightblade class that makes it the top pick? There isn't any other class on the front page.

Is it because they have critical healing linked to their damage output? It just seems like any other class would be able to do the same thing with the right gear. So it must be something specific to one of the NB class skill lines.

Renato90085

30%buff
and can debuff mobs/boss dmg close 0

fred4

Could be Major and Minor Cowardice from Mass Hysteria and Power Extraction respectively. Enemies in IA have low weapon and spell damage, making these effective debuffs. I'm under the impression, though, that for higher arcs you need an Infused Weakening Enchant, Attuned Enchantment visions, and possibly Torug's Pact or Heartland Conqueror to handle the Marauders. Enchants can scale to to a much higher debuff, e.g. 1K to 2K, or more.

So I'm not sure. Healing on NB with Dark Cloak can be very strong, or healing from damage with Swallow Soul, Sap Essence and possibly Soulcleaver.

It may also be possible to avoid certain attacks with Shadowy Disguise, even though prolonged cloaking tends to reset fights. Maybe this resets fights to get rid of Marauders, I'm not sure. Maybe it resets the blob shards targeting you, as it does with "taking aim" archers in, for example, Maelstrom Arena.

Haven't tried to solo IA on NB myself, so I'm not sure which of these factors is the big one, if any, or whether there is something else.

YandereGirlfriend

Dark Cloak goes really hard if you're health-stacking in IA.

Also access to rare buffs and debuffs, like others have said. The overall class toolkit is just very well designed for the solo experience.