The sentences are messed up and confusing. They read:
When dealing Fire damage the target has to make a DC 8 Con saving throw or becoWhen dealt fire damage the target has to make a constitution save or be set alive.
First, the obvious typing error (becoWhen).
Secondly, is it a DC 8 Con s/t, a constitution s/t (their Con) or a s/t of DC8 against their Constitution. It's a tad ambiguous.