These hearts are sometimes(rarely) dropped by enemies(some enemies don't drop them at all). They can be found throughout the game and they refill one heart of life.
These stars are dropped by enemies more often than the hearts. If you collect five of these stars, it will refill one heart of life. The star on your in-play menu will show the amount of stars you currently have.
You can find these bottles of medicine in hidden rooms throughout the game. They refill some of your life, or all of it if you have a low amount of heart containers. To use the collected medicine, press PAUSE, then UP on the d-pad, and select the medicine.
This ID code is given to you by Dr. Jones' island assistant named Baboo. It allows you to start up Sub-C(Dr. Jones' submarine) and start sailing the tropical seas.
Chapter 1 Weapons
An unlikely weapon for a hero battling against evil aliens... but remember, Mike is an expert pitcher! This is your first weapon in the game, and it'll stay with you throughout the game. At two points in the game, your yo-yo will be upgraded(or replaced) to another level of power and it'll look cooler. I bought a yo-yo because of this!
These will be acquired about mid-way through the first cave. You only have a certain amount of them. They are also twice as strong as your yo-yo, but they cannot be thrown as fast.