Raynor:
Ability leveling:snipe, save, save, snipe, 2 chrono rift, save, ulti. then max snipe chrono rift and ulti. change ulti for max sticky bomb if there are a lot of pimped heroes.
ITEMS basic:glim, energy relic, get SCEPTORS!, sylvannas shoes.
Tech:any tech is fine, personal preference is toss with raynor as you get your money by using hero and not army.
Tassadar
Ability leveling:immolation, evasion, save, immolation, evasion, save. ultimate. then max immolation,evasion and ulti, 3 on the other abilty(thinking of switching to 3 immolation since you get axe and make money solely with ultimate so no need of immolation)
ITEMS basic:circlet of nobility x2, glim x2, then save for mana/hp potion(should be used when surrounded on ur ultimate, they will try to kill you and when youre about to die use lols) you will spend a lot of money in potions but the level experience you get its whats worht it. then work towards a sceptor and leech life. axe gaunts and ulti claw
ultimately you want ulti claw, axe x2, gaunt, leech.
Tech: tech between lvl 11-12 because youll be based.
on another note, get fish and sprock with this hero to not make the enemies aware you are getting fed and protection of your base.
Rex
Ability leveling:ultra, scorpion, save, ultra, scorpion, save, ultimate. then go max ultralisk and scorpions and ulti. then mutalisk at 3.
ITEMS basic: this hero lacks always mana so get energy relic x2 war drums
Tech:you usually want either stalkers to blink on you when you ulti or zerg tier. i rarely go terran because rex wonders a lot from being melee and often gets killed when microing marauders.
important way of using rex after level 7: make youself inv. dont cast ur summons. wait till you see a hero in middle go inv and then cast all your summons, garanteed kill.