Concentration Skill

General Skills Rules:

• Taking 10: If you are not threatened or distracted you can take 10 on a roll.
• Taking 20: when you have plenty of time, 2 minutes or more and faced with no threats or distractions, you can take 20. This does not count as a ‘natural 20’ and indicate automatic success. Generally this takes 20 times longer than normal. You can’t take 20 on any check that has consequences for failure.
• “1” Rolls: When you roll a natural 1 on a skill check, roll D20 again. SUBTRACT this number from your check.
• “20” Rolls: When you roll a natural 20 on a skill check, roll D20 again. Add this number plus the 20 to your check.

Concentration (CON)
Requires: part of an action or in response, Retries: No
Avoid Distraction: when you would potential distracted while attempting an action; if any action would provoke an AoO, if would require a concentration check. If you succeed, continue as normal, if you fail, the action fail and is wasted.
Cast Spell, use spell like ability or use skill defensively to avoid AoO DC 15 + 2 times the spell level. A roll of a 1 indicates failure regardless of skill ranks.
Gaining your Psionic Focus is a DC 20 concentration check that requires a full round action.
Action and DC:

• Casting A spell DC: 10 + spell level
• Taking continuous damage  DC: 10 + ½ damage
• Damage during an action DC:10 + damage 
• Distracted by non-damaging spell DC of distracting Spell
• Vigorous Motion DC:10 
• Violent motion DC:15
• Extraordinarily violent motion DC:20 
• Entangled DC:15
• Grappled or pinned DC:15+ 2x SL 
• High winds + rain or sleet DC:5
• Wind = hail, dust or debris DC:10 
• Severe weather from spell DC of spell
• Psionic Focus DC:20