A Lu Shang's Fishing Rod or an Ebisu Fishing Rod is required to be able to catch Gugrusaurus and Lik. The latter is the reward from completing this quest so if you are doing this you will not have it but a friend can catch the fish for you as they can be traded or sold.
The Penguin Ring is recommended to be able to more easily weaken the more stubborn Gugrusaurus and Lik. If not using one of the EX baits, it is also recommended to use an Albatross Ring at the same time to allow yourself enough time to land the catch.
Level 78 Fishing is required in order to get the Serpent Rumors key item, so that is the absolute minimum level required to begin this quest; however, fishers lower than level 90 fishing will have a very difficult time reeling in the fish necessary for the quest. Close to level 100 fishing is highly recommended.
You will break your rod a lot trying to catch these fish, so consider either raising woodworking or bringing a woodworking mule along for repairs. Woodworking skill level of 68+ can repair a Broken Lu Shang's Rod, but you can possibly use up an entire stack of crystals or more per repair. Suggested skill level of 74+ for a better success rate. Please also be aware that you will lose your rod if you are repairing it when the Ferry docks, if a monster attacks you, or if someone casts a spell or song on you during your synth.
Some have had to turn in over 1000 fish for an item while others have received it after as little as 1 fish. Current estimates as well as tracking here on wiki have put results of both Opal Silk and Saber Shoot at about 1% each.
Irmilant has asked you to bring the two base materials required to craft a legendary fishing rod. These materials seem to have found their way into the bellies of sea creatures that still elude the finest fishermen.
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