The difference between the superior and the inferior in any kind of situation, be it real life or gaming, is diversity and flexibility. Especially as an addition to a team. So here is one Mordekaiser-build to make an example of this.

pros:
+Engager
+Multiple damage source. Damage-reduction not as effective.
+Independant

cons:
-Vulnerable to CC if not used properly

I choose mainly per-level-runes. Sure you get exponentially less stats for each level considering how much more experience you need for each level. Regardless, a stat is a stat. By level 6 those runes are equivalent to the stats of flat runes, doubled by level 12 and tripled at level 18. So just keep your *** intact til level 6 and all is fine. Which should be considerably easy if you just play passive (difficult doing nothing huh? :P). And with his shield to boot harassers should be your least problem.

Quintessence:
1xHP 1xAD 1xMPen

Marks:
AD/level to get most out of my Q

Seals:
HP/level runes.
I considered using HP5/level runes but since they don't really add anything in the heat of a battle and I go with Spellvamp it's no longer required.

Glyphs:
You can go with either AP/level or CD/level. Both are great.
For a tankier hybrid you can use MRes/level and then change seals to Dodge/level or Armor/level.

Since your Q is the core of you Hybrid stats it's vital to have.
I know most people rather pick E but it doesn't gain from the AD and it's weak 1on1 unless you're standing with enemy minions. Q on the other hand doubles the damage to a single unit at the least.

Hextech Revolver (*HR) for survivability and relatively free spells.
You have ghost so don't upgrade these babies too soon.
for some health regeneration
... Bilgewater Cutlas (*BC) for chasing and ensuring kills.
Hextech Gunblad (*HG) let the hunting begin.
Your AP/AD is balanced by now so it's the perfect timing.
This item is the only "non-hybrid". Mainly cause I don't "really" want to go with lots of HG:s and it makes sure I have balance with my BC later on.
You got your AP increased now so it makes perfect sense.
hunting wabbits.
by now you should've taken 2nd tower or atleast be close to doing so. If not then I assume your team is lacking. I also did some easy maths, the odds for wether or not you'll meet 2+ stun/silence/taunt/fear is about 50% so get this to rid of most CC as well. Do [E]+[Alt-W] as soon as you get back up. Play safe til you have it back on CD.
The armor and magic resist should now be +68 +68 because of Lich Bane. coincidence? :)

This is a general view on builds that apply to any champion. So pay attention to the opposition. Such as Karthus or Heavy CC. In which case; more than 4 stun/fear/silence/taunt.

Ignoreand get these instead:
for Anti-CC and do alt-W asap in Team Fights.
for Karthus

1v1:
HG->[D]->[R]->[F]->[Alt-W]->[Q]->BC->[W]->Spam anything that gets off CD. You'll love how you won't need to target anyone specific since you dmg everything around you. This is why I hate chars like Akali, Shaco and Irelia. Imagine Cho'gath with 6 stacks on top of his 4 TeamMates. Good luck with targeting.

Level 1
Hit as many Minions as possible along with champions with your E. Don't engage til level 6. Period! Let your laning-partner die if that's what it takes. Be a good sport and notify him/her about this.

Level 4-5
I usually find myself recalling at lvl4 or 5 for HR+Boots and 1 Health Potion to take Red buff unless your lane is threatened.

Level 6
If you have more health than your opponents I'd say go for it. Just make sure you don't go alone and that there is no ss in mid-lane. And don't be desperate. If they get away with 10% by their tower so be it. Patience.

Mid and Lategame
Red lane:
Fundamentally you'd never go past the middle of your lane unless you have a SightWard by the water when you lane alone by this time. Do this til 1st tower is down. Let minions do the dirty work and protect them in any way you can. Hit towers by level 12 at least.
When you go for 2nd tower you place 1 SightWard at the flank of mid-lane. And 1 by the bushes of their Blue buff so that you see them come early enough in case you'd steal their buff.

Blue Lane:
Different to Red lane would be where you place your 2nd SightWard. Which is by the red buff. Most accurate description of placement would be exactly between red buff and 2nd Tower. By the crossroad. This honestly give you a 66% survival rate which can be 100% if you place a 3rd SightWard between Dragon/Baron and their Red buff. Another crossroad.

Plan A:
Notify your team of your Lane-pushing strategy. Which is:
"MY PLAN: I will push my lane ENTIRE game. This ensures 4v4 in mid-lane or they lose towers. Any less than that ensures our kills in mid."

Plan B:
This applies where your team doesn't have a tank, or have a feeding tank. Stick with any support you have. Like glue. And ensure he/she doesn't die. You may die alot in team-fights, but you have no stack-building items and any outcome is the result of your team's inevitable strength.
Just take it easy and only push beyond mid of a lane when you have 5 champions doing so.

Thank you for reading this far! Feel free to commend and insult anything you may find enlightening and stupid. See you on the battlefield!