There are two ways you can set stats for mage
1. Put 4 on intelligence, it gives you a high magic attack, but your physical and magical defence is lower, so you need a lot more HP potions.
2. Put 3 on intelligence and 1 on spirit, it allows you to do critial hits and sometimes when monsters attack you with physical attack, they get harmed too. So, your magic attack is lower.
You can also use attack, defence, and possess pet to cover the weakness of your character.
Attack pet :
When you reach lv 20, a Wierd Mushroom is probility the best for attack pet, they have the highest attack of all lv 0~40 pets and they have good dexeterity too. It is best when it is supreme star 1 and above. Usually a supreme 1 Wierd Mushroom have about 300 in strenth growth. And to catch one Supreme Star 1 Wierd Mushroom usually need around 60~80 Wierd Mushroom Soul Orbs and Book of Pet Appraisal. In all 1 Supreme Star 1 Wierd Mushroom cost about 10 gold if you catch itYou should ONLY add sturdy to your Wierd Mushroom. When you reach lv 40, you could buy a new pet - Android 18. Android 18 has the highest dexeterity growth and it does range attack, but their strenth growth is lesser than Wierd Mushroom. Therefore, you need to have a lot of heath or a defence pet that has a lot of health. A Supreme Star 1 Android 18 costs about 80~150 gold. You can also try to catch a Supreme Star 1 but it takes too much time and gold. You can add some sturdy to your pet for higher damage, but i suggest to only add dexterity to your pet for more critial damage. Android 18 is as good as Wierd Mushroom until it is at a very high level or Supreme Star 3 ~ Perfect so you don't really need to buy it if you don't have the money.
When you reach lv 20, you can either get a (Metal) Shrimp. 40~80 (Metal) Shrimp Orb and Book of Pet Appraisal can give you a Supreme Star 1 (Metal) Shrimp. But since the (Metal) Shrimp don't be your main Defence pet, its okay to have it in Genius Star 3. You should add all physique to your pet. It don't really need to be a Metal Shrimp, any kind of Shrimp/Lobster you find at Karugarner is fine. When you reach lv 40, you should get rid of your (Metal) Shrimp and buy a Supreme Star 1 Steel Dragon for about 80~2000 gold. Do not try to catch one becuase even if you can get its HP down to 10% or lower, it is still almost impossible to catch a Supreme Star 1; it will proility use up 250+ gold. Add all physique to your Steel Dragon. You do have to buy this pet if you don't want to get killed before you can heal yourself.
When you reach lv 20, if you are a 4-intelligence mage, it is best to get a Supreme Star (Giant Land) Dolphine. The Dolphine has the most spirit, therefore the most magic defence will be added to your character when possess. 60~80 (Giant Land) Doplhine Soul Orbs and Book of Pet Appraisal can give you a Supreme Star 1 (Giant Land) Dolphine. In all, it cost about 10 gold if you try to catch it. Add only add will to your (Giant Land) Dophine. The kind of dophine doesn't really matter at all. When you reach lv 20, if you are a 3-intelligence mage, it is best to get a Supreme Star Rotten Corpse Bug. The Rotten Corpse Bug has the most intelligence, therefore the most magic attack will be added to your character when possess. 60~80 Rotten Corpse Bug and Book of Pet Appraisal can give you a Supreme Star 1 Rotten Corpse Bug. In all, it cost about 10 gold if you try to catch it. Add only add wit to your Rotten Corpse Bug.
If you want to fight monsters, bosses, and instances by yourself, I would strongly suggest you to be a 3-intelligence mage with a Supreme Star 1+ Rotten Corpse Bug as possess pet. You will get the most XP by doin so, but the least chance to gain an (quest) item by doing so. Also when you are at a higher level, it is almost impossible or need too much potion and time to finish quest and instance by yourself. If you want to fight monsters, bosses, and instances with at least a holy or dark priest that heals, i would strongly suggest you to be a 4-intelligence mage with a Supreme Star 1+ Rotten Corpse Bug. You will be able to hit the most within your group and won't die easily because of the priest. At higher level, you need a holy priest that can improve the magic and physical dfence or else you will get killed in 1 hit. If you want to fight monsters, bosses, and instances with someone else so monster wont only focus on you, i would strongly suggest you to be a 4-intelligence mage with a Supreme Star 1 Giant Land Doplhine or a 3-intelligence mage with a Supreme Star 1+ Rotten Corpse Bug. You will do the highest damage in your gruop (unless there is a 4-intelligence mage with a Supreme Star 1+ Rotten Corpse Bug). You will also not killed so easily by a boss. i strongly suggest you to be one of this kind of mage because it is always powerful. You should always have a Supreme Star 1+ Steel Dragon as your defence pet if you are fighting a boss or instance if you dont want to get killed easily. If you arent the level yet, get a (Metal) Shrimp or any pet with high HP and high physical defence. If you got money and don't like the pets im talking about and want to be a stronger mage, you can try to buy some lendary pet. A perfect one i would sell for 20000 gold.