This section contains some specific information on certain things in the game that the game itself doesn't always communicate too well, as well as some recommendations on how to make fully exploring the game more efficient.
Quests that are not found in any particular location, but received by e-mail or calls.
Double drop rate: Equipping Drop Rate Up +3 and Drop Rate Up +4 plug-in chips together is the most efficient way to nearly double (+90%) the amount of items the enemies drop when killed. The earliest opportunity to farm the low level versions of these chips is from the Small Flyers during the roller coaster ride in the Amusement Park; you can also buy them from the shop in Pascal's Village. Playing the game with drop rate maximized from the start can save you a lot of potential material farming.
Critical attacks: A critical attack can happen randomly with any strike and deals 500% damage. Equipping Critical Up chips increases the chance of it happening: a Critical Up +8 chip gives +30% critical chance, which means you get 500% damage every three hits on average — the equivalent of having +60% damage overall. You can further enhance this by using a weapon with "Critical +" effect (see reference for a list of weapons with this effect).
Counter attacks: You need to equp a Counter chip to be able to counter enemy attacks (the method is in the chip's description). Nearly every melee attack in the game can be countered, and with higher chip versions the move returns damage back to the attacker.
Auto-Collect Item: Becomes available for purchase in route A from the same NPC who gives you the Scanner. Makes items auto-collect just like $.
Item Scan: Available for purchase in route B after receiving e-mail about new stock in Resistance Camp. Makes items show up as blue dots on the minimap.
Most quests in the game are clearly marked on the map: a red dot for where the quest is available, and then a red diamond or area for where you need to go to fulfill it. However, there are some exceptions where the game doesn't mark everything, or the quest isn't registered as a quest.