STUN STUN STUN... when with allies stunning anyone without a shield (excluding portable shield like tarvold's) can be your priority to help your teammates clear the point
Try to avoid Close Quarter Combat with Mal damba since his weapon and cobra stun is effective at close range.and remember,every good Mal damba always throw out atleast 1 ammo for ready stun reload
When ulting as Mal'damba be careful of shields and the cart, both of those can stop your ult from being as effective as possible by blocking it from hitting anyone. Try and make your ult detonate above the cart.