the strongest, most easy, counter to LB
any mage
but the counter to LB is ITEMS
if lb is on the other team. you dont need cdr. you dont need morellos. that becomes overrated and not needed vs a LB
instead. if LB is on the other team. pick your mage. but build 2 rod of ages, and a warmogs, BEFORE boots
by the time warmogs is done. you have now purchased a lvl16 garen passive. making you regenerate all the health between LB's combos. and LB cant burst you because your so damn tanky
honestly. i feel all AP items have been destroyed so hard that just stacking rod of ages is probably the strongest way to go most situations
get 3 rod of ages, warmogs, liandry, ludens on your mage of choice. and you have tons of damage, tankyness, and your all around just a beast