Nightblade tanks can be good. To answer your questions:

- when an expansion is on the PtS but not live, the patch notes are in the public test server section of the forum. There are usually 4-6 iterations as they hone the changes, then whatever the final changes are will be posted in patch notes in the main section when the expansion drops.

- the major change for NB tanks is the ability to select a morph of cloak that doesn’t offer stealth ( @ZOS_wrobel - weak dev skills, dude) but instead heals for 33% of max health. Scaling off max health for this will be huge for tanks. Previously vigor was the burst heal...roughly it would offer a NB tank ~5000 health. The new skill ( @zos_wrobel which is nice, but has been put senselessly on the wrong ability because the dev team is lazy and makes poor choices) will heal for maybe 20k health...quite a boost.

Tip: if you’re a new player with a low level blade and no champion points, you may want the invisibility over the heal while you’re lower levels. Invisibility is really helpful in pushing through content faster, and grinding. If I were leveling a new NB, I would take the invisibility morph then recast it later when I was building the character as a tank.

- I’m not sure why someone would say siphoning attacks / leeching strikes is bad now. One is for magic, the other is for stamina. It’s a fantastic resource return ability, and Summerset isn’t nerfing it as far as I know.

- more broadly speaking, you can have tank in mind as your long term goal, but you don’t have the run the character as a pure tank as you level and grind. Keep this in mind - ESO doesn’t force you to make permanent decisions that lock you into a roll. You can kinda level everything, then have a vet who can pretty easily flip between tank, dps, etc.

A stamblade tank will need a lot of champion points to be a very good tank. They get a lot of survivability and defense from these. Which is fine...all classes need a lot of CPs to tackle the endgame content you’re referring to. So you might approach the character as more of a tank/dps in working them up to vet and then earning your first ~300 CPs. At that point you could start to really focus on tank building.

Some basics aimed at helping you get to NB super tank:

- level heavy and medium armor. You can level all three if you want. But with this character you’ll likely end up wanting medium for a lot of generic PvE stuff, then mostly heavy when you tank. Medium offers a lot of dps. When I run my dk and Templar tanks in overland grind PvE, I throw on medium to speed things up.

- this character might benefit from all four physical weapons in different situations. Feel free to dabble with them all, and level them all at least a little. When you get to vet, use your enlightenment (see guides section) to bring all of these lines to 50.

- legerdemain: I recommend that all new nightblades level their leger to 16 to get the 40% reduction in sneak cost. It’s worh the investment. Every once in a while, go to the ships docked at daggerfall (few npcs) and steal everything. Fence it all. Do this ~12 times and you’re there. As a bonus, higher legerdemain offers you better rpg on chests and steals.

- one of your longest grinds will be undaunted. You want to get to undaunted 9 to unlock the powerful passives...one which is going to give you more resources, which this character will want. Once you open undaunted (level 43), start running both the delve dailies and normal dungeon dailies. You need about 125 to level this line...it’s a long grind. So start it as soon as you can.