There are three kinds of Iconic armor: Tier 1, Tier 2, and PvP.
Tier 1 - Obtain from doing duo's & Hard Mode Alerts - There isn't that many duo's though, prepare for grinds.
Each one nets you 2 Marks and each can be run once a day. If you do all 4 of each, you complete another mission which nets you 2 more.
Tier 2 - You get Tier 2 armor by doing 8-man Raids..(such as batcave) you can run each Raid once a week and they give you 4 marks per each run.. that is all the info i have on that until release.
PVP - These sets are obtained from doing pvp arenas- You get 2 Marks if you win and 1 Mark if you lose. PvP Armor is the only known way to get the Toughness stat; Toughness is your damage mitigation in PvP. Defense does the same thing in PvE. (remember defense stat is useless in pvp)
If you want to learn more about stats such as health, defense etc please see my website i have got a full explanation there about stats.
so..
Some examples:
If you choose Tech for Heroes(Batman) Then the Steel Suit you see in the HQ is Tier1, the Batman Suit is Tier 2 and the Robin Suit is for PVP.
You get 2 Marks if you win and 1 Mark if you lose in pvp arenas.
If you wanted Steel's armor from HQ he is the Tech PvP set.
First: Make a Tech hero.
Second: Level him to 30.
Third: You will need about 350 Marks from PvP Arenas. Each time you lose, you will get 1. Each time you win, you will get 2. (grind, grind and ugh.. more grinding)
the marks of victory are earned from all of the arenas and raids at lvl 30.
These are needed for the top armours.
One of the top PvP sets is going to cost you about 810 marks.. or if you want lower pve quality you are talking 350.
Once again check my web for detailed stats and tips:
The Stats: HERE
The Pvp Tips: HERE
Just remember that your char may be great as a pve, but the main stat in pve is not used at all in a pvp match and could put your in a really bad position, so try and not to focus to much on the wrong stat and pick your armours wisely 
Kudos for that mate
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