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Playable and balanced Codex

Adds playable Codex into the barracks on a reload of any save. (It's recommended to play the starting mission first and then enable the mod.) Unlike most aliens from other ''add character'' mods, this unit is actually balanced around level-ups and xcom class system:

YES. You can level her up
Starts with 2 hp (3 on Rookie)
Reduced mobility and only 55+5 aim
Does not have Psionic Rift
Clones are extremely weak

This Codex also has access to unique weapon: "Precision Beam Rifle". It's a mix between assault and sniper rifles that may be used by all classes, deals decent damage, has 2 upgrade slots, provides +5 aim and squadsight ability, can fire after spending one action point and doesn't have a close range penalty. NOTE: If this weapon is used by regular soldiers, the firing animation will be bugged.

Tips:
Try to teleport on the high ground if possible. This will compensate low aim.
Unless you got a useful upgrade, try to rush Nanoscale Vest. It can mean the difference between life and death at the beginning of the campaign.

That's basically it. Enjoy!

Huge thanks for the creator of this guide that I used to create the mod: https://www.reddit.com/r/xcom2mods/comments/45rwal/how_to_add_aliens_to_the_armory_tutorial/