Why is Riot recommending the blue supp item when ancient coin is 10x better
Why is riot recommending supp items when 
this is better?
Nvm i lost a game with that build, Yuumi just sucks :/
Why are you listening to riot's recommended items on literally any champion?
Spell thief finishes faster and has better Mana Regen if you play her properly also gives AP.
Beyond that she's new and her recommended items aren't set in stone yet.
Frostfang gives on hit damage, so it directly buffs her passive. She's not a dot mage. Those items take a very long time to buy on a typical support budget too, your Q already slows so Rylai's is redundant
Yuumi is an enchanter that emphasises a champions ability to kite and chase, she uses her passive to survive lane and then late she can be a real monster with ult, zoomies and her Q
