Kill a Sectopod on the same turn you encounter it (in Single Player)

Kill a Berserker in melee combat

Recover the Blacksite Data

Sabotage an alien facility

Skulljack an ADVENT Officer

Sell goods worth 1000 supplies to the Black Market (Can span multiple games)

Apply a PCS upgrade to a soldier

Kill a Viper who is strangling a squadmate

Make contact with a region

Play through all areas of the game

Kill a Sectoid who is currently mind controlling a squadmate

Complete a Rumor

Complete the tactical tutorial