Tekking
Tekking is a process done to convert unidentified weapons with specials into better, identified ones. Weapons with specials are found in an unknown or untekked state, denoted by "????" in front of the weapon name. There is a Tekker located in each episode's shop who can identify, or tekk, a weapon for 100 meseta. A weapon's special, attributes, and grind can vary when tekking. It is not uncommon to have to tekk a weapon multiple times to obtain the most desirable weapon special and photon attributes.
Specials
For non-rare weapons, each unidentified weapon comes with a hidden special that can vary when being tekked. For example, Arrest's activation rate is 80%, Seize's is 64%, Hold's is 48%, and Bind's is 32%. Tekking a weapon to have the most desirable special can make it much more effective. Specials can be tekked up or down one level, so an untekked Seize weapon can be tekked up to Arrest or down to Hold. Rare weapons have a set special which does not change when tekking. See the list of special attacks for more information on special attack levels.
Photon Attributes
Weapons have five different photon attributes: Native, A.Beast, Machine, Dark and Hit. Percentages in Native, A.Beast, Machine, and Dark will increase a weapon's damage to the corresponding enemy types, while Hit increases attack accuracy. These percentages can vary from 5-90% in each category. Photon attributes can be tekked up or down by 10%, but attributes of 0% can't be altered during the tekking process. This means that incorrectly tekking an item can lead to a -5% attribute. While additional percentages can be added to Native, A.Beast, Machine, and Dark, a weapon's Hit attribute can only be modified during the tekking process. Tekking a weapon to have the most desirable photon attributes is an important part of the tekking process.
Grind
A non-rare weapon's grind can be tekked up or down by 4. Rare weapons have a set grind of 0, which does not change when tekking. A weapon's grind is the least important aspect of tekking, since grind can easily be added to a weapon by using grinders. Obtaining the desired special and photon attributes should be prioritized when tekking.
Special Cases
Quests such as Claire's Deal require specific weapon specials to craft items. In this case it is often beneficial to tekk down a weapon's special so that it can be used to craft a new and better item. For example, to craft a PB/Increase, one of the necessary components is a Seize Launcher. An Arrest Launcher has a much higher activation rate for paralysis, but it is beneficial to tekk it down to Seize to obtain a component for a PB/Increase.
It can also be beneficial to tekk a weapon's attributes to make adding percentages to it more cost-effective. It costs 20 Photon Drops to add 5% to a weapon's photon attribute and 1 Photon Sphere to add 30%. Tekking a weapon's photon attributes to 70%, 40%, or 10% in order to use Photon Spheres can save a considerable amount of Photon Drops.