From StrategyWiki, the free strategy guide and walkthrough wiki

Power-ups are temporary in game items that help Caim during ground missions. They can either be found by getting chain combinations of 10 or more, or by opening treasure chests. Power-ups that drop from enemies are temporary and will disappear if left untouched for 30 seconds or so.

Contents 1 Small Green Orb 2 Large Green Orb 3 Orange/Red Orb 4 Black/Red Orb 5 New Weapon

[edit] Small Green Orb

Restores a small amount of health.

[edit] Large Green Orb

Restores a large amount of health.

[edit] Orange/Red Orb

Sends out a shockwave knocking over and damaging all nearby enemies.

[edit] Black/Red Orb

Causes Caim to deal double damage with his weapon.

[edit] New Weapon

Only found inside treasure chests, new weapons are identified by some type of blade present within the contents of the chest. After getting, the new weapon will be revealed and available after the current mission is complete.