Sizing up an enemy in 4th Edition

There are three ways to aproach an enemy

Intelectually, Charismatically, or Head and Wall aproach

Knowing is Half the battle - In this case, A skill challenge would lower the to-hit dc on the enemy. The more you know about the enemy, the easier it is to take them down.

Cast Doubt - Taunting and engaging the enemy prior to combat can lower attack mods and their confidence (if they have some kind of willpower defense), but every hit they inflict restores their confidence -- and their attack mods.

Head and Wall - Engage the enemy before it has a chance to make preparations, attack the problem head on. Attacks can make the enemy lose their weapons, become more vulnerable to disarm, more likely to surrender, enemies tend to be more spread apart.