Update: Since a lot of people seem to come across this page looking for a leveling guide (sorry, mine isn’t finished yet), here’s a link to one that does a decent job at showing you how to reach the level cap quickly with any class or job.
Guildleves are rectangular plates made of colored crystal that are set into a metal frame. The picture shows one of Eorsea’s saints or guardians. These leves are given to the adventurer by the guild master. The adventurer will then be able to select one of the leves that best suits their needs. From here the adventurer will be able to collect these leves as one would with collective cards and use these to begin quests and adventures.
Guildleves are quests that adventurers can perform each day to earn experience, gil and items that will help the adventure continue throughout their journey and dungeon. The adventurer has the option to complete these quests individually or within a group with other adventurers as only one leve is required to reap the benefits and rewards from that particular quest.
Guildleves are designed for you to create your own adventures every time you play so the possibilities are endless.
Battlecraft leves are designed for your disciples of war or magic classes. These quests require the adventurer to complete certain objectives within a time limit. They will need to seek and destroy certain monsters throughout the time given.
Tradecraft leves are designed for those who craft. These quests require the adventurer to deliver specific crafted items to the required client (NPC)
Field craft leves are designed for gatherers or disciples of the land. These quests require the adventurer to complete specific gathering related tasks within a time limit. These tasks consist of visiting various locations or seeking items like harvesting, logging or mining.
Grand company leves are combat quests that are only available to members of a specific grand company. The adventures are to speak with an officer of the grand company to be granted these quests.
Once the quests are completed the adventurer will be able to return with new rewards and continue onto the next adventure.