Skill Point

Skill Points are a resource in Call of Duty: Ghosts Extinction and Call of Duty: Heroes. 
==Extinction==
Skill Points are an essential resource in Extinction.
As players progress through maps and complete challenges, they will gain skill points. These skill points are used to upgrade the various aspects of one's own character that they select before the game starts. There will be a message on the HUD reminding players if they have skill points to potentially spend. Because challenges award skill points, players are encouraged into trying as well as they can to complete any and all challenges so as to earn more skill points.
The player can purchase an Armory upgrade to receive one free skill point to start the game. Otherwise, all players start off with no skill points to start each match, and skill points do not carry over to the next match; each match has players start off with a clean slate.
Usage of skill points is vital for keeping a level playing field with the Cryptids. As the Cryptids become stronger and more plentiful as the game goes on, skill points allow players to become stronger themselves, through making deployable items more effective and/or making the player themselves more effective. 
Some of the later upgrades may require more than one skill point to purchase, with some of the strongest upgrades requiring as many as three skill points to purchase. Because some upgrades have an inflated cost, even under optimal circumstances where players get every skill point possible, it is not possible to fully upgrade every part of a player's kit in a single match, although players can come pretty close. Players using one of the Relics that disable certain loadout items, those being Mortal, No Machines, and/or Earn Your Keep, are unable to upgrade those items and can thus focus on using their skill points elsewhere, with the potential of fully upgrading the limited loadout available to them.
On Hardcore difficulty, skill points gained from simply finishing hives, obelisks, generators, or area objectives on Exodus are no longer awarded, and skill points on Hardcore difficulty can only be earned through challenge completion. Thus, players need to spend their skill points much more wisely.
==Call of Duty: Heroes==
Skill Points return in Call of Duty: Heroes. They are obtained through destroying structures in PvP and through daily rewards. They are used to activate and upgrade Heroes' skills.