This build is meant for fights against fully ad or AD fed teams. Your sustain with this build is completely unmatched. Everyone of your skills will be healing you like you've been never been healed before. Your ultimate most likely will heal you for 50% of you entire life, however CC is still a problem, especially if the enemy team has any kind of AP carry. In the case, considering your life will be going up and down and up again in a second, you should aim for the AP's and only then ult their AD carry. Because of the high number of hextech gunblades, your ad should be reasonable enough to keep you alive during those scary seconds while all your skills are recharging.
Because of that, I strongly recommend the use of Heal and Ignite, which means you won't be able to flee. Once you engage TF, you must kill of them, orthewise you'll die, unless your team has some CC as well.

1V1 Strategy

I do not recomend engaging on 1v1 without support of enemy minions - YES YOU HEARD RIGHT - as Mordekaiser (I dunno if you're an new Mord player or not) the more enemy minions around you, the more shield you'll farm, and once your build is up, 1v1 with minions around you and your enemy should not prove to be hard as you'll be contanly healing yourself up.

GO FOR THE PENTAKILL, MORDE!

If you play Mordekaiser like I do, then you're the kind of person who doesn't trust your team at all. In that case, once your build is up, I suggest you sell onde of the Hextech Gunblades and add a Guardian Angel instead. If you're already fed enough, go for the 5x1 and aim straight for that AD carry who's ruining your team. Once he's down you'll be probably be down too (let's face the truth 4 guys attacking you with this build is pretty hard to hold even with your shield up), however if you were strong enough to kill their carry with Children of the Grave, then you'll be dealing tons of dmg while you're down on the ground, so hold your summoner's Heal for the time of your rebirth and finish them off with a massive span of skills.