https://youtu.be/_eTBvGK2Ask

In case anyone is still wondering how to successfully clear Skirmishes in the Night Market:

I played through each one with tips and a bit of other advice, the perspective is from the tank view. But I speak on the other roles and their duties a bit as well. I got more detailed in the text guide than the video actually, in order to cover things which without the visuals might be less clear or understandable. So if you are a text guide enjoyer, that was for you!

This guide is late due to life/family issues, but I decided to finish it anyway for those who asked originally, those who have joined the event late and for future use.
ESO Night Market: Skirmish Guide

This guide covers the three main skirmishes in the Night Market. These events can be challenging, but understanding the core mechanics will significantly improve your success rate.

1. Skittering Precinct (1:01)

Mechanic: You must clear spiders and use fire from braziers to burn piles of skittering spiders. Spiders will constantly web over these braziers, so players must prioritize cleaning the webs to keep the fires active.

After that bar fills up to 100%, the zone will have activatable Dreg piles. Simply walk up to them, activate the Dreg and slowly walk it to a nearby Brazier. Other players should do their best to keep the Brazier's lit and the Dreg carriers safe. So kill as many mobs as possible, taunt them off Dreg carriers and clean webs off the Braziers.

Boss Tips: The final boss has a dangerous charging attack that can one-shot players if they don't dodge-roll out of the way (7:25). As a tank, ensure you have some massive mitigation or invulnerability if you plan to eat the hit. I was unable.

General Tip: This event can become overwhelming quickly. If your DPS is not top-tier, managing the braziers is the highest priority to avoid getting bogged down by adds.

Additionally, the Roaming Roksa boss will likely show up during this, in fact the event takes so long it's almost certain. So kill it before hand, or be ready for the additional trouble. The boss itself is a pretty normal tank and spank, with the most dangerous ability being a beam which sprays the current agro target for a ton of damage over like 10-11 seconds so you will need a lot of mitigation or healing as a tank for this. Non tanks are hard to keep alive.

The other mechanic of the Roksa is that is spawns little light orbs which explode, but they are easy to clear. So just clear the 5 or so orbs when you see them periodically just to avoid needless damage or deaths.

2. The Parch Skirmish (11:29)

Mechanic: The objective is to collect blue electrical orbs dropped by defeated mobs and use them to activate broken anti-weather pylons.

Secondarily, bring the elementals over to the Pylons in the second phase once the arc circle is complete. And kill them on top of the Pylons to charge them up as the Elementals power disperses.

Boss Tips: The main boss performs a massive expanding red circle attack. If the circle reaches its full range, it will one-shot everyone inside. You must activate the pylons with orbs to stop the expansion (15:06). These are the same orbs which drop from elemental mobs, and the Pylons will have a green circle indicating their readiness to accept the orb charge.

Important Note: Watch out for the roaming worm in the area; avoid getting swallowed by it, as it will trap you until you destroy internal sacks to escape (14:28).

3. Sorrow's Friend Skirmish (18:07)

Mechanic: You must destroy pillars that are invulnerable until you defeat "Restless Dead" skeletons in close proximity to them. Always prioritize burning one pillar at a time.

Boss Tips: You will face the main spider boss alongside a "Spiral Incarnate" mini-boss. The mini-boss should be tanked to keep it away from DPS and healers, but don't waste time trying to kill it as it will respawn. Focus all main damage on the spider (23:32).

Additionally, the roaming boss here will almost certainly show up if you did not kill it before starting the skirmish event. And unlike the Roksa in the Skittering Precinct, this one had a very deadly AOE move. It will periodically spawn a void orb on the ground which has strong gravitational pull, you have to brace/break free asap and move out of the circle. If anyone hits the center, it explodes violently and will one shot most players with normal non tank levels of health and defenses.

Pro-Tip: Forming Secondary Groups (18:11)

If you find the skirmishes too chaotic or slow, consider forming a second group within your instance. (Or 3rd if you are feeling extra spicy. But beware, the 3rd group is very likely to not successfully get all 12 players in your instance. Because if there are ANY other players in the entire Night Market instance, they count toward the 36 player cap.)

Why do it: Each instance supports up to 36 players (three groups of 12). By organizing a second group, you can split objectives more efficiently and reduce the pressure on a single 12-man team.

Benefits: This is the most effective way to farm loot and favor faster. It prevents the event from scaling poorly and keeps the encounter moving, making it much easier to handle roaming bosses (like the Calamituos or Roksa) that can disrupt the main event. If your group is struggling to clear mechanics or stay alive, a second group is often the difference between a quick success and a repeated failure.

Hope this was beneficial to someone even if late. Let me know if you have any questions or input any time.

-ESO Feanor