Thanks for taking the time to answer, that all makes sense to me. Never played D&D before so trying to learn the rules as I go smile.

I assume that the DC roll that the target makes is affected by their modifier for the attribute listed as the save, right ? So in the case of the first example, they would get a -1 to their save with 8 CON?

In the case of the second example, there's no ability listed apart from "melee attack". Does that mean they don't get a modifier ?