out of fight for 15 secs gain magical shield. this item is very good e.g. for galio as it has really good health stats and the magic shield empowers his passive shield as well. It is also very good m ritem for any other champion of course
taking magic damage grants stacks, at maximum stacks receive additional mr and movement speed
deals magic damage in area around you, killing enemy deals magic damage around that area
reduces enemies mr + gives you additional mr for every cursed enemy

reduces attack speed of enemies, reduces physical damage. its very similar and cheaper option from Randuin's Omen, the only difference is Frozen Heart is used against aa champs when Randuin's Omen against critical champs like MF or Caitlyn
reduces critical damage, active slows enemies around. More expensive item than Frozen Heart but if you have enemy team comp that deals hard critical damage its very useful
every 5 secs in fight deal magic damage to enemies healing for 250% of damage dealt. this item could be used for high health champs who deal damage at the same time like Sett, Volibear or Cho'Gath e.g.
deals magic damage in area around you. very solid option against heavy ad team comp
reduces healing, deals magic damage to attacking enemies. as an item with both armor and health stats its very good option for champs that scale either with HP or resistance
its good item if you need your priority fed teammate kept alive because it transforms 12% of damage onto you while you will be healing and both of you contributing

gives you shield
at maximum stacks increases magic and physical damage resists
spawns zone that slows enemies and deals magic damage

reduces attack speed of enemies, reduces physical damage. its very similar and cheaper option from Randuin's Omen, the only difference is Frozen Heart is used against aa champs when Randuin's Omen against critical champs like MF or Caitlyn
its good item if you need your priority fed teammate kept alive because it transforms 12% of damage onto you while you will be healing and both of you contributing
reduces enemies mr + gives you additional mr for every cursed enemy
gives you shield
spawns zone that slows enemies and deals magic damage

quick restoration of health outside fight, gives movement speed
3 secs in fight chargé powerful attack that grants you 12% permanentmax health of damage dealt, size increasing

vs lots of cc, reduces magic damage
reduces attack damage