The first cities were carved from the wilderness in the name of Erathis. With her boon, the same sense of teamwork allows you and your allies to overcome any obstacle.
Lvl 3: 680 gp
Lvl 8: 3400 gp
Lvl 13: 17000 gp
Property: When you use the aid another action, you grant your ally a +4 bonus rather than +2.
Power (daily * healing): Minor action. An ally within 5 squares of you can spend a healing surge. That ally also gains a +1 bonus to his or her next attack roll.
Level 8: The ally regains 1d6 additional hit points.
Level 13: The ally regains 1d6 additional hit points and gains a +2 bonus to its next attack roll.