Here's an example - as you can see the DMGBASETYPE: slashing effect (1) changes the base damage type (2) from piercing to slashing when the damage action is rolled (3)
Note, from the Wiki effects page: Replaces the damage action base damage type with the new type. It is assume that the first damage type of the first damage instance is the base damage type.
https://www.fantasygrounds.com/forum...chmentid=59728

