Murdock's Ultimate (R) has a huge range and the ability to shoot through walls, use this to aid your allies by sniping your enemies from unconventional places!
Concentrate on last hitting minnions during early-game, try to keep the minnion wave closer to your tower then the enemy tower. This will make the lane safer for you, and leave the enemy hero or heroes open for ganks from your teammates.
Get a Sage's Ward, or any other shadow ward you'd like as early as possible.
Golden Tip, Khaimera's don't be haters! :D. Play a swapper deck, ( 3x 5 instant filler cards which you swap for stronger cards near and if game reaches late game) Ex. Madstone Gem x2 ( both filled with 1x Power) Red Eye Nitro x2 ( one: 3x Minor wound, one: 2x wound, minor kinetic) now early game when you face 1on1 Khaimera for some reason they think they are indistructable haha, Lay down E somewhat behind you, when khaimera pushes you, use it to defend as sort of turret base, or walk back as if u let him think u mist it, when he jumps over it to get you push him in with your shield, basic + q + basic spam + lay trap again. This makes sure u get the kills on the more ganky but fragile heroes ( Khaimera, Kalari, Dekker if he flanks for team support, Greystone). +Tip a little extra: When greystone is starting to use his ult instantly drop E right below him, when hes done ulting he's instantly stuck and your team can finish him !
Go for all +energy dmg, Murdock hits like a truck. Mid game can take out lower hp players in 3-4 basic attacks