Do feats buffing halfling's Second Chance stack?

Question

Halfling Agility is a heroic feat that gives the triggering attack a -2 penalty on its reroll. Nimble Dodge is paragon and similar to the first; It has a -5 penalty and the reroll cannot crit.

So could I use both and get a total -7 attack penalty?

Answer 1

Yes

Halfling Agility states:

Benefit: When you use the halfling second chance power, the attacker takes a –2 penalty to the new attack roll.

Nimble dodge states:

Nimble Dodge Heroic Tier Prerequisite: Halfling, any martial class Benefit: When you make an enemy reroll an attack roll using your second chance racial power, the enemy takes a -5 penalty to the second attack roll and can’t score a critical hit on that roll.

They are penalties that come from different sources and are untyped, therefore they stack. This is fair because they're both buffing a singular encounter power and could therefore be considered a waste of feats. I recommend taking simply nimble dodge.