- armor, health, an attack speed slow and a movement speed slow; and the two actives mostly mitigate each other. is a strong counter to , as it provides
- items that can reduce attack speed. The attack speed slow on and Randuin's Omen do not stack with each other, however they do stack multiplicatively with for a combined 27.75% attack speed slow. , , and Randuin's Omen are the only
- Randuin's Omen is commonly purchased by tanky melee DPS champions, especially the manaless champions like Dr. Mundo, Garen, Lee Sin, and Renekton that don't benefit from because of the mana it gives.
- Using the active on Randuin's Omen while your champion is channeling an ability will end the channel prematurely.
- Randuin's Omen's +10% critical strike damage reduction also affects magic damage " critical strikes", the abilities that enhance their damage when they meet the criteria for increasing damage, making this item an effective item against champions with abilities of enhanced damage.
- is named after former Riot employee Robin 'Randuin' Liao.
- Randuin's Omen active effect's debuff is named Black Omen, possibly a reference to the floating palace bearing the same name from the game Chrono Trigger.
- Randuin's Omen is the only item that can reduce the amount of damage taken from critical strikes.