Help me build a Illusionist Rogue

[Thanatos]

Would it work? I think its the best option for playing Trickster mythic path but i really have no idea how to build it to make it work.

[Yannir]

Not sure what you're looking for really. You're either looking at a pure Eldritch Scoundrel or a multiclass between a magic user and a thief-type, I'd guess.

[Drake]

Yeah eldritch scoundrel with some illusion feats is pretty much what you want. the archetype is basically a mage/thief multiclass.

[RedwoodElf]

Basically, you want to copy Woljif's build, and pick illusion as your specialist school.

[Neobab]

Works awesome with the Trickster mythic path.

Such a build depends on a balance : Melee vs Caster.

To put it simply, the more you go on the caster side, the more you'll have to pick favorable targets/situations for it to work properly.

Melee rogue with extra tricks : This one I like a lot and is very simple to handle. Go full rogue up to lvl 20. Take Trickster mythic path.
Tiefling works great for this build. Put max Dex, the lowest Str possible as Weapon Finesse and Finesse Training will let you use your Dex and the lowest charisma possible (if you're into min-maxing). Go for 2 short swords.
For your mythic spells, take only utility spells, as your DC will be abysmal. Use Bit of Fun as much as you can. Using invisibility, you can sneak attack casters or archers and make them disapear first turn. If you can, use another character to flank. You'll easily deal 4 attacks each for 40dmg, reducing the AC of the target, -2 Str and a lot of other funny things.

If you want to be more on the caster side, your aim will be Arcane Trickster. This one is a bit trickier.
You will need at least 3 level in Rogue and 3 level in an Arcane class (Sorcerer, Wizard...). Gnome works awesome with this build due to Gnome Magic racial trait. At level 7, you'll be able to take Arcane Trickster prestige class, that you can max up to lvl 17. Then take some more Rogue lvl or Caster level. Max Dex and put 16-18 in Intelligence / Charisma, so you'll have a decent DC. Sacrifice your strength and your constitution. You'll be unstoppable against target without will. Using invisibility, you'll also be able to deal Sneak Attack damage with your spells (which have attack rolls), which just is overpowered.

Enjoy !

[Super Cosmic Space Magnet]

Arcane Enforcer subclass of Slayer might be up your alley! While you might not have a spellbook, your Arcanist Exploits will give you the same sorta feel while letting you be a full attack bonus class, and will be able to do absolutely monstrous damage even before getting all the whacky late game Trickster stuff. Also, Trickster can let you cast spells anyways!