I love the thought of a two handed Nightblade using high damage assassin ablities from stealth and then swapping to syphon abilities to chop them the rest of the way into death. Also with abilities like teleport, charge, and immovable there is no running away once I get started. My big question is what second weapon I should use with this? Did anyone try out something simular to this and what did you find worked well with it or does any theory-crafters have any brilliant ideas?

Nightblade is undoubtedly hardest class to make build for, You have to find the perfect stamina-magicka balance to achieve good damage outcome.

If you are going to use syphon i would recommend you to use Bow , With marked for death and movement steal of siphon , haste and snipe bonus damage , they fit eachother perfectly.

They cant run from you with that build but they might not even need to, 2H is more focused on AoE so it deals low damage to single target compared to dual wield. Also one of its most important skill it the one deals bonus to low health which you already have as nightblade.

2H nightblade doesnt seem effective for PvP. And even for PvE you mostly fight aganist single monster.

Honestly this is what I am looking into. Was thinking of doing a dps/tank hybrid but then the skills just weren't meshing in my mind so I switched to a two handed tank build with inner fire --> inner beast for control. I see it as a self healing splash damage build. The only thing I am unsure of is if a two handed weapon can block. I think they can obviously with less efficiency of a shield but it gets me thinking.

Aeno

as bad as it sounds.. since you are gonna have a strong mellee presence... you can either get a ranged weapon (bow most likely) or healing (restoration staff)... not sure if destruction staff is viable or not.. it takes experimenting

Maybe 2h to open with and then dual wield? Lots of good stuff there. You should look into that.

I think with the Khajiit racial skill Carnage and the two handed skill Critical Charge that it could very well be a good combo. Sounds like fun anyway

Cas

I do know for a fact that two-hand weapons can block but are less efficient then shields. I did not get that two handers were more suited as AOE weapons then single target damage as one person stated above. I have no videos of a nightblade using a two hander in PvP but I have watched DKs one on one and it seemed to kill just fine.

I was just going through weapons right now actually to decide on a melee secondary. My main weapon is a resto staff. I was deciding between 2-hand and 1 hand + shield and chose 1 hand + shield. I wanted another gap closer which it offers but survivability was my main concern. A NB has a ton of dots if morphed that way and my damage from magicka based attacks was priority so melee dps wasn't my concern. Healing goes much further when coupled with mitigation.

Now if I was a sorc I would totally take 2-hand (and perhaps later dual). A sorc has amazing synergy with those 2 melee weapons.

If you look at the passives of the two hander skill line they add splash damage through forceful and reverse slice, cleave is cone but again you have the multi hit aspect of it.