This is a useful tip for playing disk 2 of Xenogears. At the dungeon where Rico gets his new gear, there's this monster called Hamar, who self-destructs after he glows red. The explosion is lethal but the party can escape before Hamar blows up. However, the trick here is to kill him before he blows up and he will give a special item which increases the rate of receiving rare items. (Actually, it goes to 100%.) The way to do it is to reserve some infinity or level 3 attacks until he turns red. Once he starts glowing, give it all to him. (Booster helps too!)

With the special item equipped, go to any forest & fight white snails. These creatures were plentiful in disk 1 but now they are quite rare. Killing these creatures gives the speed belt (helps gears & human battles). Besides this, there are many other special items/equipment carried by monsters. 

Sound Test:

When you are in the Yadrisil (Sandmarine Ship) go to the control room and talk to the large dolphin-like control man. Choose the top selection for a sound test. He'll keep asking the same question over and over. Select the first choice again for a new sound, or pick the second choice to leave.