[3.5] Tripped while spellcasting?

[Dragannia]

I've looked through the PHB and nothing seems to say anything about this subject. What exactly happens if you are tripped while casting a spell? Do you lose it? Do you need to make a Concentration check, and what would the DC be?

[ZeroNumerous]

There aren't any penalties for being prone while casting a spell. However, The Concentration skill lists rules for vigorous movement.

[UserClone]

I would call that "Extraordinarily violent motion" or at least "violent motion".

[Shpadoinkle]

I would call that "Extraordinarily violent motion" or at least "violent motion".

I'd have to second that.

[mikethepoor]

Plus, if the attacker has Improved Trip and succeeds on the followup attack, a separate Concentration check vs. the damage dealt.

[Epinephrine]

If an earthquake is DC20 + Spell level (as per the PHB), being thrown bodily to the floor should be at least as high.

[Myou]

If an earthquake is DC20 + Spell level (as per the PHB), being thrown bodily to the floor should be at least as high.

Don't forget that in a earthquake there will normally be debris falling on you and may be fires breaking out.
That said, I'd say DC 20 would be a fair, if high choice.

[The Glyphstone]

Don't forget that in a earthquake there will normally be debris falling on you and may be fires breaking out.
That said, I'd say DC 20 would be a fair, if high choice.

The same applies to Earthquake, the spell, which doesn't need to involve fires or debris, merely the tremors, so yeah.