This is a fairly simple build to use against teams that are stacked heavily on the AD side. your main role is tanking the ADC early game and late game you tank their team and use Shackles to stun the enemy team.

Your Runes just stack your Armor and help with being tanky. The Magic Penetration helps with your Q, W, and R to do damage. You can use AP Marks instead to boost your E effectiveness, but you won't be blocking much AP against a AD heavy team.

The 4-5-21 Mastery Page helps reduce your cooldowns and increase your mana. You can go 0-9-21 or even 0-21-9 to help with tankiness, but I've had the most success going 4-5-21.

You can choose whether to go W or E second, it just depends if the enemy team has enough CC to make a big difference or not. You want to go Q first as an initiation and then take your ultimate at the normal spots.

Instead of Exhaust you can take Heal, but I find taking Exhaust much more valuable early game so that it helps feed your ADC and a fed ADC is a happy one late game.

Your main job is the initiation of team fights. This means that you need to wait for your team to be behind you and make sure they go in when they should and know when to back off if it gets bad.