Defending Against Spellcasters, Part I

Because I'm a little worried about my ability to post a tip of the day without a change in format, this tip will be the first in a series.

There are many ways to defend against the attacks of spellcasters, some more effective than others. Let's start with the basics.

1. Position yourself next to the enemy caster to get an attack of opportunity when they begin casting. A successful hit will force a DC 10 + spell level + damage inflicted concentration check in order to continue casting the spell. However, this plan is spoiled if the enemy takes a 5-foot step outside your range, or decides to cast defensively (only a DC 15 + spell level check).