Here is the full list of all 38 Ben 10 achievements.
Completely upgrade all aliens
Cause a chain reaction of 5 exploding Bumblebees
Defeat 10 enemies as Ben
Collect half of the Sumo Slammer cards
Complete 30 Bonus Objectives
Defeat 3 enemies with a single use of Heatblast’s ability
Defeat an enemy as each of the 10 aliens in one fight
Finish the game
Defeat 2 enemies with a Weatherhead Drone
Destroy 5 objects with a thrown enemy
Defeat Queen Bee
Defeat 6 enemies with a single Cannonbolt roll
Defeat 3 enemies with a single use of Overflow’s ability
Completely upgrade one alien
Defeat a Pie Juggler before their pie hits the ground with XLR8’s ability
Defeat Zombozo
Defeat 5 enemies with a single use of Wildvine’s ability
Achieve a combo of 100
Hit 5 different enemies with a single shot from Grey Matter
Achieve a combo of 50
Defeat 10 enemies with a single Ultimate Ability
Collect a Sumo Slammer card
Collect every Sumo Slammer card
Complete “The City” in under 15 minutes
Complete ‘The Funhouse’ in under 15 minutes
Complete ‘The Scrapyard’ in under 15 minutes
Complete ‘The Hive’ in under 15 minutes
Complete ‘The Canyon’ in under 15 minutes
Complete ‘The Tornado’ in under 15 minutes
Hit 5 enemies with a single rolling Tweedledee
Reach the top of the Weatherhead Tower without falling off
Defeat Zombozo without taking damage
Defeat Queen Bee without taking damage
Defeat 3 enemies with a single Four Arms throw
Dodge Weatherhead lightning, then hit the attacking enemy by using Upgrade’s ability
Hit 10 enemies with a single use of Diamondhead's ability
Stun a self-destructing Bumblebee with Stinkfly’s ability
Defeat the Weatherhead Prime without taking damage