Metroid Prime 2: Echoes/Pickup and Key locations

There are 100 pickups in the game, each of which contributes 1% to your percent items shown in the pause screen and with the save name when you select a game to continue. The breakdown is:
 * 21 Upgrades
 * 18 Required
 * 3 Optional
 * 75 Expansions
 * 14 Energy Tanks
 * 49 Missile Expansions
 * 4 Beam Ammo Expansions
 * 8 Power Bomb Expansions
 * 4 Translator Modules

There are also 18 keys which are needed to confront the bosses of each area, but these don't count toward the item percent. Three each are needed to reach the Guardian bosses for Dark Agon Wastes, Dark Torvus Bog, and Ing Hive, and 9 more are needed to reach the final Ing boss in the Sky Temple.

The Unlock column in the following tables is a rough indicator of what will be required to obtain key or pickup. This does not take into account sequence breaking or other exploits.

Sky Temple keys
In this section we list the Keybearer instead of Unlock.