GameFAQs has two guides. I started writing one after I beat the game, but never followed through. This particular mission is quite simple: you have to find 10 relics that are scattered throughout the stage. Once you find one, you have to find the next one within a set amount of time, otherwise you'll lose. The stage itself is devoid of enemies, so you won't have any problems there. However, the stage is essentially a maze, and as you venture deeper to find the relics, the pressure will slowly drain your shield. After finding all the relics you battle The Hammerhead, who has been pestering you throughout the game, so this is your final encounter with it. After that you battle the final boss, the last Guardian.
I've beaten this stage already, multiple times in fact. I just would like to 'S' the mission, but like I mentioned, it is near impossible to do it. To get a higher rank you have to finish every mission with a set percentage on shield, treasure, and destruction; I believe it's between 80-90% for each. Not sure exactly, as it's been years since I played. The fact of the matter is the stage makes it difficult for you to accomplish this because the remaining treasure that you can dig out to increase your number is deeper underground, meaning your shield will get depleted. The standard strategy is to dig up as much treasure as possible before hunting the relics down, then battle both bosses without losing any shield. I've accomplished this every time, but it still wasn't enough. Just like this stage has no enemies, it also doesn't have a single health pick up, so it truly tests you.
Truly underrated game, by the way. Anyone reading this that hasn't played it, give it a try.
