CD Reduction/Frontman
since grock's ult is so long to cooldown i invented this cooldown reduction + tanky/survivavilty build, it can help to enhance tank's confident to engage since you have a almost undying build + cooldown reduction at the same time, that would be so OP if you maximize the overall potential of this build
Engager/Tanky
Chosing this emblem set would help grock more harder to kill, because Firmness can give you a 6 extra magic and physical defence, plus the tenacy that increase your physical and magic Defense by 15%(most effective when your engaging or your a front man that recieves all the enemys damage, and lastly is the brave smite that helps you recovers 5% of your max HP when you hit enemy with your skill, thats so tanky right
Battle Spell
Since Grock is so overpower in terms of initiating, chasing and in CC, Grock will need Vengeance to reflect enemy's damage, it will Help's your teammate to kill enemy's much easier.
before lvl 4 you need to help gold and mage first, then when you gain lvl 4 go to bottom lane and help the exp, so he can help you in enganging and after that, expect the victory
tips for using grock: leashing is important, give your core an oponents vision, help your exp when your lvl 4(for faster set and snowball in fight) then expect the victory!!
Best With Arlott
arlott is a perfect match for this, once you complete your set or engage, arlott will help you set more or stun more the enemy using his ult, and let your damage dealer do the killing, you can also do the arlots ult first, then your second and ult, that would be a perfect combo
Watch Out For Kalea
kalea would be a good counter for grock, when grock uses his ult, you and send you airborn, once you get the ground, lift grock with your ult, but that would be so risky