There are all the differents way i used to play cassie .

Impulse
Blast Shot
Blast Shot has its damage increased by 150 and its Cooldown decreased by 2s.
Level 1

Big Game
Disengage
For 4s after hitting an enemy with Disengage, your weapon shots deal an additional 8% of that enemy's maximum Health as damage.
Level 1

Tumble
Armor
Increase your maximum Health by 250.
Level 5

Incitement
Dodge Roll
Reduce the Cooldown of Dodge Roll by 4s if you hit an enemy with your first weapon shot after using Dodge Roll.
Level 4

Onslaught
Dodge Roll
Activating Dodge Roll heals you for 150.
Level 2

Drain Life
Blast Shot
Heal for 150 over 2s for each enemy hit by Blast Shot.
Level 2

Quiver
Weapon
Increase your maximum Ammo by 2.
Level 2

Level 3

Life Rip
Weapon
Your weapon shots gain +30% Lifesteal.
Level 3

Haven
Armor
Reduce the Damage you take from Direct and Area of Effect attacks by 18%.
Level 3
This build can be played in any situations and can be easly adapted to the ennemies's team .

Big Game
Disengage
For 4s after hitting an enemy with Disengage, your weapon shots deal an additional 8% of that enemy's maximum Health as damage.
Level 1

Territorial
Disengage
Reduce the Cooldown of Disengage by 5s.
Level 5

Onslaught
Dodge Roll
Activating Dodge Roll heals you for 225.
Level 3

Incitement
Dodge Roll
Reduce the Cooldown of Dodge Roll by 3s if you hit an enemy with your first weapon shot after using Dodge Roll.
Level 3

Tumble
Armor
Increase your maximum Health by 150.
Level 3

Sky Warden
Disengage
Heal for 125 after hitting an enemy with Disengage.
Level 1

Level 3

Life Rip
Weapon
Your weapon shots gain +30% Lifesteal.
Level 3

Haven
Armor
Reduce the Damage you take from Direct and Area of Effect attacks by 18%.
Level 3

Wrecker
Weapon
Your weapon attacks deal 90% increased Damage to Shields.
Level 3
Take this build only against two or more tanks . The main problem is that it required aim .

Impulse
Blast Shot
Blast Shot has its damage increased by 150 and its Cooldown decreased by 2s.
Level 1

Blast Shower
Blast Shot
Reduce the Cooldown of Blast Shot by 2.5s for each enemy it hits.
Level 5

Drain Life
Blast Shot
Heal for 375 over 2s for each enemy hit by Blast Shot.
Level 5

Onslaught
Dodge Roll
Activating Dodge Roll heals you for 150.
Level 2

Incitement
Dodge Roll
Reduce the Cooldown of Dodge Roll by 2s if you hit an enemy with your first weapon shot after using Dodge Roll.
Level 2

Tumble
Armor
Increase your maximum Health by 50.
Level 1

Level 3

Chronos
Armor
Reduce the Cooldown of all your abilities by 30%.
Level 3

Life Rip
Weapon
Your weapon shots gain +30% Lifesteal.
Level 3

Haven
Armor
Reduce the Damage you take from Direct and Area of Effect attacks by 18%.
Level 3
If your aim is not that good or if there is no tank take this build . Spam the Blast Shot !

Exaction
Dodge Roll
For 8s after using Dodge Roll, your next weapon shot's damage is increased by 30%.
Level 1

Onslaught
Dodge Roll
Activating Dodge Roll heals you for 300.
Level 4

Incitement
Dodge Roll
Reduce the Cooldown of Dodge Roll by 4s if you hit an enemy with your first weapon shot after using Dodge Roll.
Level 4

Somersault
Armor
Reset the Cooldown of Dodge Roll after dropping to or below 60% Health.
Level 4

Quiver
Weapon
Increase your maximum Ammo by 2.
Level 2

Fatal Sign
Weapon
Increase your Reload Speed by 12% for 5s after getting an Elimination.
Level 1

Level 3

Chronos
Armor
Reduce the Cooldown of all your abilities by 30%.
Level 3

Life Rip
Weapon
Your weapon shots gain +30% Lifesteal.
Level 3

Haven
Armor
Reduce the Damage you take from Direct and Area of Effect attacks by 18%.
Level 3
Play this build only for fun , it has been nerfed and nerver play is on ranked .
Take Big game only against two or more of these champions .
Buy wrecker only against two or more of these champions .
Buy Bulldozer only against three or more of these champions .
Buy Blast shields only against two or more of these champions .