Here is the full list of all 39 Outcast - there are Second Contact achievements worth 1,000 gamerscore.
Defeat at least 20 soldiers in Motazaar for Ashkar.
Defeat 250 soldiers.
Find the Mon in Shamazaar.
Obtain the Mon in Okasankaar.
Destroy the company of soldiers located in Zorkatraz.
Obtain the Mon in Okaar.
Complete the organ puzzle in Okaar.
Kill the Achondar.
Kill 25 Krakits.
Kill all the gamors in the Okaar arena.
Reach the region of Okaar.
Help Zern fix the boat light by providing a piece of helidium from Motazzar.
Unlock the wheel to enter the Darosham!
Set Shamaz Keb free.
Defeat 150 soldiers.
Defeat more soldiers to convince Zot to stop paying taxes.
Help Sadar fix his boat using a Zeedog plant.
Achieve the highest level of reputation by helping the Talans.
Kill the beast in the water behind the temple of Ka.
Kill the gamors far to the east of the village.
Destroy the boats in Shamazaar to weaken the soldiers!
Help Heza repair his well.
Reach the region of Okasankaar.
Talk to 25 important Talans.
Damage the rift bridge to slow the soldiers down.
Travel 10 times through Daokas.
Defeat 10 soldiers using dynamite.
Reach the region of Motazaar.
Deliver a Twon-ha for Zolass.
Reach the region of Talanzaar.
Use dynamite on a chest.
Find a Shamaz and convince him to heal Ilott.
A worker at one of the temples wants the Yods to clear away the debris.
Defeat at least 20 soldiers for Maar.
Fill your backpack with over 250 rounds for your UZA-SH1.
Obtain over 300 rounds for your HK-P12.
Find Shamaz Zeb and speak to him.
Complete all four tests with Jan.
Complete the stealth tutorial in Ranzaar with Jan.