Level quests are unlocked after a new level is reached and only when all previous level Quests have been completed. With few exceptions, the head quest of each level must be completed before the second and third quest are presented. For example Pushing Back the Dark is offered at level 3 or higher and only after completing A Man Called Smith.
Ship level quests are also unlocked after a new level is reached and only if the previous head level quest and the previous ship level quest are completed. For example the Life on the High Seas is offered only after reaching level 8 and only after completing Fresh Faces and The High Seas.
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