Retrofit

Modification is a feature added which improves a ship beyond just breaking the ships limits or strengthening her stats. This uses special blueprints gotten via quests, daily log in bonuses or drops on hard mode maps.

Current list of ships available for modification
Cygnet, Ajax, Abukuma, Hammann, Portland, Fortune, Suffolk, Langley, Bogue, Ranger, Long Island, Leander, Shoho, Javelin

When you first access the Modification screen of a ship, your option is very limited with only access to a single upgrade, this so far is an armor upgrade that boosts a ships max HP.

Once you have unlocked the first attribute, those connected to it can then be unlocked. There are a variety of unlock-able attributes that can increase a ships stats, increase a ships proficiency on equipment slots and even eventually unlock a new skill for the ship. If an attribute has multiple skills connected 'before' it then they all must be learnt before it unlocks.

As you unlock and get further into the Modification tree, attributes require more and rarer blueprints. The attributes also start coming in multiple levels, only unlocking the next attribute once maxed. You are also required to limit break a ship to get deeper into the tree, a low level ship with no limit breaks cannot go very far down into the Modification tree.

Once Modification is complete, the ship gains a new CG and ranks up in rarity.