An overview of pets
This would seam quite a simple area to cover but because it spiders into to so many other aspects of the game it is a source of great confusion for many players,
We will begin with simply choosing the right pet for you.
Combat pets:
A combat pet is a pet that will assist you in battle, think of them as an extra party member.
choosing a combat pet is like choosing your class, what do u want from it?
My personal recommendations:
Dex pets: these benefit from a naturally high evade and crit rate so in general make good companions for regular PvE encounters, the are low cost to maintain because they are least likely to consume pet recovery potions.
Vit pets: they are like walking HP potions if skilled correctly, they are least likely to die at a crucial time and weaker players can use these to taunt some of the attention away from their main character.
Str Pets: the all out brawler, expensive to maintain in potions because they are the most likely to take on the damage but will increase your kill rate because of the sheer weight of damage they can lay down.
Int Pet: these should generally maintain a distance from the action and lay down huge magic damage, there only flaw is they are the most fragile, Glass cannons come to mind.
Sprt pets: this is your mana battery, if skilled to do so they can rescue your MP during those dangerous times, they are good buffing pets and still allow for decent damage, they do benefit from the highest natural defense of any pet type.
Ok so once you have your combat pet sorted, what else do you need?
Fusion Pets
After the demigod scenario quest line, pet fusion changes the game.
Now you are able to absorb the power of your pet for limited periods.
how does this affect you?
Well picking what pets you need for fusion means knowing your characters strengths and weaknesses.
most players carry 2 pets for the purposes of fusion, one to bolster there main attribute and one to cover their weaknesses,
we will use a mage as out first example, mages cause huge amounts of damage, but often draw agro beyond what they can handle, so to counter this, fusing with a good Vit pet would allow them to have enough HP to survive.
But, for those times when damage isn't a worry and you just want to lay down insane amounts of damage, fusing with a pure Int pet allows your to bump your damage output excessively.
Special Note: Only a Spirit pet boosts Phy/Mag Defense so it is recommended for All classes to have 1 good spirit pet just to fuse when things get to tough.
Now that your have your chosen pets how do you make the best use of them,
Fortify levels: combat pets will be taking damage, regardless of type so fortify levels reduce the amount of damage the pet takes,
Growth: this relates to how much the base attributes increase per level, it should be improved before leveling a pet to allow for maximum strength. it does not appear to be retro active so waiting till you have the cash later appears to be a waste of every level you put onto a pet.
(Unless you plan on ascension)