You are able to inlay runes into the holes on equipment after punching, runes will improve your power and strength.
How to inlay?
Go to visit the NPC who is called: Hodge in the City of Heroes. Place your equipment into the Rune Inlay interface and put in a rune with the corresponding color of the hole you place it in. You may only inlay one rune in each hole.
There are 3 different kinds of Runes available in DOAK. Attack related rune, protection related rune and combined rune
Where can I obtain Runes?
You can obtain runes by doing activities (Shortcut key [I]), or killing monsters from Instances, or by killing Skeleton Kings.