by OedipussyRex
Any time you would cover an action with a marker, you cannot combine it with another action that would be covered. For example, you cannot use the +3 Navigation round booster and the free terraform power action to build on that distant planet you've had your eye on. You would need to use QICs to span the distance.Note that one-time-per-round actions (cover with marker) are not the only actions that cannot be combined, just the easiest to visualize.