Frozen Heart is a legendary item in League of Legends.
- aura. is gold efficient without the
- items that can reduce attack speed. The attack speed slow of stacks multiplicatively with and , for a combined 27.75% attack speed slow. , and its upgrade, , are the only
- As with other aura items such as , debuff can give away potential ganks.
- tank champions because of the high amount of armor and cooldown reduction but can also be useful for tanky support champions. is an item best suited for
- mana helps compensate for his mana troubles, the armor will make him much more durable and the aura will improve his already awesome dueling. is also an good user of , as the
- In general, this item is good on:
- Tanks and bruisers that are generally sitting on the middle of enemy team during teamfights, as they make the best use of the aura due to this (by affecting as many enemies as possible); and they are generally mana hungry. Examples include , , and .
- Champions in general, that work well with cooldown reduction, have mana problems, and make very good use of the passive for extra dueling potential. Examples include the aforementioned , as well as , , and .
- Even if you don't need to slow the enemy's attack speed, the extra armor, mana and cooldown reduction may come handy against every AD champion.
- attack speed reduction aura, that indirectly reduces damage potential. is not recommended on , because usually equipped with a and in order to deal damage he needs to be attacked, the more basic attacks he received the more damage output he will have. has an
- This item can also be bought by manaless champions, should they wish the combination of cooldown reduction, armor, and attack speed reduction in one item. It may be better to buy and/or , though, as the mana from is completely wasted.
- For its combine cost of 800, gives 150 mana, 25 armor, 10% cooldown reduction, and an attack speed reducing aura.
- helps counter DPS carries like , , and ADCs in general, since they all rely on auto-attacks and the decreased attack speed will reduce their damage output.
- stacks with in 700 range, effectively doubling damage. Useful on mage supports like or .
- The attack speed debuff affects champions, minions, and monsters, except for the Dragon, Baron Nashor, and Vilemaw, as they are immune to crowd control.
- The old icon  used for was the same icon from the popular online MMO game, World of Warcraft, used to represent a Citrine gem. In this game, the gem appears orange.
- The item's description "Warning: Do not thaw!" is a reference to the item Eye of Skadi from the mod DotA: Allstars, whose description contains exactly the same line.
- The Harrowing celebration. It has the same stats as the , just a different name and picture. was a seasonal item for the 2010
- Currently, Frozen Heart offers the largest amount of armor from a single item.