
Instance got 2 goals:
1. Survive
2. Kill as many waves as possible
There is no final goal. Instance does not have an end.
In other words you can stay inside for hours killing new waves of mobs - if you manage.
With each new wave your time between waves shortens and goes down to 30sec at wave 20 and next ones
Instance will end if:
1. All team members die
2. Team fails to kill any mobs within a specified time limit (so you can't hide and wait)
Team size: 4 people
Entries per day: 4 entries
Each wave of mobs consists of either:
1 boss (in most cases a dragon) and 3 elite mobs
or
6 elite mobs
There's over 20 different, unique, wave set-ups.
Spawning wave set-up is taken at random - so it might happen, for example, that you get 2 same wave set-ups (same boss) 2 times in a row. In other words you never know what is coming next.
add: Each mob in the instance in unique - it got it's own defensive and offensive stats and skills.
Each mob got a skill (elites) or set of skills (bosses) that he will use.
They also provide a very broad set of "how you want to die" choices

Fair warning: some of this skills do hit very hard
Inside the instance you have:
Buffing crystals (work very similar to jotun ones) once all four crystals are used they will respawn after some time

Egg - killing the egg will reset skills of everyone in the team. Egg will respawn after some time as well

Guard Tower - static mob that spawns at a random times to annoy u

EDIT: Mob is moved to the middle of the platform (from the top).
So in short - get a team of 4 go inside, use crystals when you need, use egg when needed kill waves until you get bored
Rewards:
Each elite mob drops:

Each boss drops:

There's also a very high chance to get from the boss:

At the end of the instance you gain might and Bags containing food (1 bag for each stage you won)
so for example if you finish 10 stages everyone in the team gets 10 bags each
Promo vid: https://www.facebook.com/NotAionOfficial/videos/1541064022619409/