There is a Skirmish Event going on now, scheduled to end March 11. Here are some things I've figured out:
Each day, Nedda Pinleaf in the Bree, 21st Hall, and Ost Galadh skirmish camps, offers a Skirmish Assault wrapper quest. The quest lists 4 or 5 skirmishes that have an extra encounter-like mob called a Harbinger. For the event, there is an auto-bestowed quest, Skirmish--Ill Omens, to complete the Skirmish Assault quest on 12 days.
To get credit, you must:
- Pick up the daily quest from Nedda Pinleaf before doing the skirmishes
- Turn the quest in to Nedda Pinleaf once completed
- Do all but one of the skirmishes in the list.
- You must qualify for the skirmish (minimum level, owning the content, any prerequisites to open it, etc.)
- Defeat the Harbinger in the skirmish.
The Harbinger may appear during or after completion of the skirmish. Solo t1 120, the mobs had about 500k morale and were not difficult for hunter Michaleo but were not trivial for minstrel Wrytune. Do not exit the skirmish before defeating the Harbinger.
You may do the skirmish on any tier and any size (solo, duo, small fellowship, fellowship, raid). It has been said but not verified that you get credit as long as the skirmish is within +/-5 of your level. It is not necessary to do the regular skirmish encounters.
Although on the first day, the quest reset but didn't change at the usual 3AM server time reset, they plan to fix it so that it resets and changes at that time. This means you must complete the required skirmishes and turn the quest in before 3AM server time (or do the next day starting after 3AM server time).
It is claimed that, for skirmishes where the Harbinger appears before the end of the skirmish, you can defeat the Harbinger and get credit without bothering to complete the skirmish. I haven't tried that.
There is a deed Banisher of Ill Omens for doing 60 total skirmishes (in the Deed Log on the Skirmishes tab). For some reason, it does not count all of them. Although I did 3 of the 4 and completed the quest, the deed only showed 2. Cordovan suggested it may be because the Harbinger was defeated too far from its spawn location. Apparently the "Do not retreat from combat" warning means don't kite. Or it could be some other bug.
You get 2 Tokens of Ill Omens per Harbinger and for the Skirmish Assault quest. So far, the only things you can buy are cloaks and pets.
Completing the Skirmish Assault on 12 days rewards with a super-essence box, like the Yule Seasonal Instance did. Doing all of the skirmishes on t3 supposedly rewards another super-essence box. Those boxes are bound to account, suggesting that lower-level characters could get boxes for higher level characters on the same account.
I'll post anything else I find out. Feel free to add to this thread.