basically the monster is a planetar and i would like to add 10 Paladin levels and 2 Mythic Tiers. i would like to know what are the main things i must do. in paizo webpage it says this, but i don't understand.
Next, add the class levels to the monster, making all of the necessary additions to its HD, hit points, BAB, CMB, CMD, feats, skills, spells, and class features. If the creature possesses class features (such as spellcasting or sneak attack) for the class that is being added, these abilities stack. This functions just like adding class levels to a character without racial Hit Dice.
My main questions are...Are all this stats just added to the stats of the monster? in the rules they don't tell exactly how to adjust..they just say...make all the neccessary additions, well the word "addition" seems a little OP for me here. so i just add BAB to the current BAB of the creature so it gets 10 BAB more for paladin levels?
Yes, you simply add everything from the class onto the monster.
In this case, you'll add +10 BAB, +7 Fort save, +3 Ref save, +7 Will save, +10d10 hit points (with 10*CON), +10*(2+INT) skill points, and the class features and spellcasting for a 10th-level paladin. In addition, you'll add 5 feats for gaining 10 HD, and a total of 2 ability score points for reaching its 20th and 24th HD.
In addition, the rules say to add +4/+4/+2/+2/+0/-2 to a monster's stats when you give it class levels. This change represents changing from a 3-point-buy (the default for monsters) to a 15-point-buy (the default for NPCs with regular class levels).
Be aware that the finished planetar paladin will be approximately a CR 26 monster.
Yes exactly my friend, a CR 26 is exactly what i want, i want to kill one player :D that's retribution for trying to destroy the whole church organization even after he has been pardoned once.
thanks for the help.
Just a small suggestion, instead if giving the Planetar 10 levels of Paladin casting I would add +3 levels of cleric casting bringing the Planetar up to CL 19.
(Paladin-3)/2 = cleric levels; is how I got that. Just a suggestion.