If "Once per Turn" is on your own card (eg on your Influence card) then your Dreamer can use this card once per Turn.
If this entry is on a common element (e.g. Item), then it applies to all Dreamers - i.e. if one Dreamer uses it, then no other Dreamer can use it in the same Turn.
So just to make sure: The luck die is a common element and there is 5 of us playing. So does that mean that the whole team can only roll the luck die once per turn (not including rerolls)?
Boosting your intent is one of your basic actions (rulebook pg 13). It is an individual action not the whole team so every player can roll the luck die once per turn.
> It depends.
If "Once per Turn" is on your own card (eg on your Influence card) then your Dreamer can use this card once per Turn.
If this entry is on a common element (e.g. Item), then it applies to all Dreamers - i.e. if one Dreamer uses it, then no other Dreamer can use it in the same Turn.