Question: Ongoing Damage and stacking

[Cacophonik]

Yes, another one. :)

According to the PHB, ongoing damage of the same type (or untyped) does not stack when applied to the same target.

What happens when a single character is attacked by a pair of critters who each have the following powers:

Spoiler:

Creatures in question are Plague-Changed Ghoul Eaters, from Dungeon 161.

Claws (Standard, at-will)
+18 vs Armor Class; 2d6+5 damage, and the target is immobilized (save ends).

Gut Tongue
When the plague-changed ghoul eater damages an immobilized, stunned, or unconscious target with its Claws attack, the target also takes ongoing 10 acid damage (save ends).

Is the second power usable only once - until the afflicted character saves against it - in which case it can be re-applied the next time the first power hits under applicable conditions?

I think that's the way the RAW would interpret the situation, but it doesn't really make sense that way, (to me, anyways...) given the power descriptions.

[Logos]

No

When a target has ongoing damage of the exact same type or greater or lesser versions, they get rolled into each other.

You can still spam the ongoing attack, the same ongoing damage just gets rolls into itself. Something that would prevent other monsters from using a simular attack would probably require a PREREQUISITE line along the lines of PREREQUISITE: Not already affected by this power or something like that.

For example, monster 1 hits with ongoing Acid 10, Monster 2 Hits with ongoing Acid 10. The Target only has ongoing Acid 10 (once). The benefit of multible monsters of the same ongoing damage is ensuring hits (attacks may miss, but more attack rolls = more hits) which will in turn result in more damage. (if you get hit with ongoing 10 every round, their is no way to 'save' out of it, because even if you save, your hit again, and ongoing does damage (at the beginning of the round) before you save (at the end of the round).

For the greater or lesser its more or less the same its just saying that if you have ongoing fire 5 and ongoing fire 10 you deal with the ongoing fire 10.

Its in the phb, and the references are in the ask a stupid question thread if you want to confirm.