We only have one Lord of War in the Codex, and by we, I mean the Ultramarines. It's Marneus Calgar, and he's still a nasty piece of work. He's lost a few abilities, including the ability to unlock multiple Honor Guard squads, which is no longer necessary since they're an Elites choice. He also no longer allows your army to choose to pass or fail any Morale test, which is a shame as that was a great ability. Finally, he no longer re-rolls his armour penetration rolls in close-combat.
Even with those losses, Marneus did get some improvements to make up for it. He now gets to pick his Warlord Trait rather than roll 3 and pick one, so that's a definite improvement, and he still allows your army to use one extra Combat Doctrine during the game. However, the biggest change is that the Gauntlets of Ultramar now strike at initiative, so while Marneus isn't as much of a support character as he was, he is much more of a wrecking ball in assault. Bringing 6 S8 attacks at I 5, Marneus Calgar will make a mess of anything he charges. If you really need to do some damage, he can pick up Furious Charge via his Warlord Trait.
His only available option is to switch out his artificer armor for Terminator armor with a teleport homer. Unless you're transporting him in a Rhino, I would take the Terminator armor for 2 simple reasons. First, it's a much better model. Second, it allows him to move and fire his Orbital Strike, which is the only way an Orbital Strike is useful.