Final Fantasy XV being a RPG obviously has an upgrade tree (not to be confused with Skills which are different in the game) known as the Ascension Grid. As players level up or perform various actions throughout their adventure, they gain AP which can be used to unlock new abilities and upgrades in the Ascension Grid.
The Ascension Grid is divided into eight sub-trees: Armiger, Magic, Recovery, Techniques, Combat, Teamwork, Stats and Exploration. The first few upgrades of most of the trees are pretty cheap and players will easily unlock them within the starting couple of hours.
However, as each tree opens up further branches, it can be difficult to plan for upgrades especially when their cost continues to increase rapidly and there is no way to refund the AP once it has been spent. Would be really bad if someone unlocked an upgrade that cost 99 AP only to later realize they didn’t actually need it.
To get things going, players should focus on spending AP on the Combat grid to increase their effectiveness in fights as well as speed up XP earning. To that very end, Blink and Airstep upgrades are extremely important and should be learned as soon as possible. They allow players to stay mobile during fights and avoid a lot of enemy damage so there is less reliance on potions to survive.
Similarly, Link Up from Teamwork grid is also very important and should be learned at early levels. Link Up increases link-strike damage during combat encounters which means enemies will die quickly when players perform combos with their team mates.
Once Link Up has been learned, players should focus on boosting the HP of Noctis and his companions through the Stats grid. Upgrading this grid quickly unlocks the ability to equip two accessories on all characters which can be a significant stats boost.
Another cheap grid upgrade which should be focused on earlier is the Exploration grid which allows players to earn more AP by camping through Happy Camping. Similarly, Appetize and Roadrunning also provide useful buffs early on in the game.
Once these basic upgrades are done, players can start investing in specialized moves for their companions in order to replace the basic Piercer, Mark and Tempest. Gladiolus should learn Cyclone, Prompto should pick up Starshell while Ignis with Enhancement can buff Noctis’ attacks with elemental damage to which their current enemy is weak against.
Upgrades to Magic and Armiger are entirely up to the player and their playstyle but the above mentioned upgrades should be focused upon earlier for an easier experience in the game.