The Incarnate Trials are missions well-suited for Level 50s--both of them require you to be at your best, and to have a strong group of similar Level 50s to run them with you. To get any of the higher-tier Slots, you must complete one of them.
A Word of Warning from Wiser Players than Myself
Based on the research I've done, and from hearing from other veteran players about the difficulties of both Trials, the best idea is to go in with a well-balanced team of 8 players, or a well-balanced league of 48 players. Healers are great, but you'll also need enemy neutralizers, ally buffers/enemy debuffers, and damage-dealers of all flavors.
Team or League leaders should be prepared to explain what each Trial's phases are about, and what each phase's objectives will be BEFORE taking on the Trial. Since many of the phases of each Trial are time-sensitive and unforgiving of inexperienced players (such as myself, lol), teams and leagues will need to be coordinated and careful.
The Individual's Responsibility
As a Trial participant, you'll want to be prepared with a full set of Inspirations as best suited for your character. Some characters don't need a ton of Awakens and Break Frees, and some characters have no need for Enrage or Sturdy; this is up to your discretion. You'll also want to have all your powers slotted with the Enhancements and Enhancement Sets you need, so that you're in top fighting shape.
You will need to watch team and league communications for changes in plans, coordinated attacks, and planning ahead for defeating objectives. You should also be mindful of the other players--do not just rush in, heedless of everything else, and expect that everyone else will follow you. This will lead to a Leeroy Jenkins-esque tragedy. (I should know--I've Leeroyed enough in my City of Heroes life. XD)
To know which Trials you need to complete for your particular hero, read up on them on ParagonWiki's List of Incarnate Trials page.
Incarnate Trial Rewards
- Completing any part of an Incarnate Trial gives you an Astral Merit.
- Completing a whole Trial gives you an Empyrean Merit, but you can't get this Merit more than every 20 hours.
- When you complete the Trial, you'll get to choose from one of the following rewards:
- All common Incarnate Components
- All Uncommon Components
- All Rare Components
- 10 Incarnate Threads