Building Your Javelin shows all the relevant tutorials within Tutorials main section of the Cortex.
Collection Details
A total of 6 cortex entries make reference to Building Your Javelin.
These entries help understand players on how to customize their javelins' combat loadout and appearance. It also shows the rewards that can be unlocked by improving the javelin.
Customizing Your Javelin's Appearance
See Cortex Entry: Customizing Your Javelin's Appearance for More Details
A javelin's appearance can be customized using the Forge. New paint jobs and appearance options can be applied to suits, giving them a unique flair and style.
New appearance options are unlocked with Coin and Shards in the Forge or at Prospero's store.
Prestige can be earned by completing Challenges or engaging the Weekly Alliance System. Any appearance options you earn, unlock, or purchase can be used by any of your pilots. Once unlocked, the items are yours forever.
Items in the Vault
See Cortex Entry: Items in the Vault for More Details
All collected items are found in a Fort Tarsis repository called the Vault. Access the Vault to view collections and salvage any unwanted items for spare crafting materials.
Vault items are also accessible at the Forge and can be equipped by multiple javelins at the same time. They cannot be shared between pilots.
Only a limited number of items can be stored in the Vault. Warnings will appear if the Vault is nearly full.
Loot
See Cortex Entry: Loot for More Details
Receive loot by successfully completing missions and from sources like defeated enemies and treasure chests. The specific loot is only revealed once an expedition is completed, but includes javelin upgrades such as weapons, gear, and components. Once revealed, items can be equipped at the Forge.
When defeating enemies, there's always a chance that loot will drop. Powerful enemies, Elite enemies, and Legendary enemies all have an increased chance of a drop.
Treasure chests will also drop loot. The quality of the chest determines the number of possible loot drops. Chests can be found while exploring during missions or Freeplay, but also upon completion of Freeplay events or major Stronghold encounters.
Successfully completing missions automatically adds loot to a player's backpack, which resolves as normal after completing the expedition. Bonus loot is added by successfully completing a mission after using Quickplay.
Loot drops have a maximum rarity that is determined by the players current pilot level. At Level 1-9, drops are 
Uncommon rarity; Level 10-19 are 
Rare; Level 20-29 are 
Epic; Level 30+ are 
Masterwork. At Level 30+, there is a small chance that 
Legendary items will drop instead of Masterwork items.
Pilot Level Rewards
See Cortex Entry: Pilot Level Rewards for More Details
Pilots level up by earning experience points (XP). At various levels, a variety of awards are unlocked, including Forge slots, match consumables, and new javelins. Javelin unlocks are account-based.
Level 2—New Javelin Unlocked!
Level 3—Weapon Slot Unlocked!
Level 4—Component Slot Unlocked!
Level 5—Support Slot Unlocked!
Level 6—Component Slot Unlocked!
Level 8—New Javelin Unlocked!
Level 10—Consumable Slot Unlocked!
Level 12—Component Slot Unlocked!
Level 14—Component Slot Unlocked!
Level 16—New Javelin Unlocked!
Level 18—Component Slot Unlocked!
Level 20—Consumable Slot Unlocked!
Level 23—Component Slot Unlocked!
Level 26—New Javelin Unlocked!
Level 30—Consumable Slot Unlocked!
Level 30—Grandmaster Difficulties Unlocked!
Unlocking New Javelins
See Cortex Entry: Unlocking New Javelins for More Details
Upgrading at the Forge
See Cortex Entry: Upgrading at the Forge for More Details
Equipment swaps and javelin upgrades can be done at the Forge once guns and gear are found in the world. As a pilot levels up, more javelin customization slots will unlock.
Equipping higher-level items will raise your javelin's power level, which is reflected as a rarity level. Higher-level suits find rare and powerful items more often, and can tackle missions at higher difficulty levels.