Invisibility Question

[Joust]

So a PC casts invisibility on himself, and a few rounds later he is surrounded by critters that know he's in the area. The PC gets hit by a lucky swing and takes some damage. Does he stay invisible after taking the damage if he does not attack? A second critter (a Slaad) casts See Invisibility, casts a spell at the PC, and does damage to the PC. Again, does the PC stay invisible as long as he does not attack?

 

[Dr. Zoom]

Yes. He only becomes visible if he attacks or the spell ends.