Some CDR Items that could be added (all with passives)
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100 AP 15 MR 15 Armor 10% CDR Unique Passive: After dealing spell damage gain 20 Armor and 20 MR for 3 seconds.
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80 AP Unique Active [Toggle-able] : Upon casting a spell, gain 10% (15% ?) cooldown reduction, increase your spells mana cost by 7% and gain 15 ability power for 4 seconds, ability power can be stacked up to 3 (or 4?) times, and mana cost stacks up to 4 times.
( 's passive in "reverted" when the item is combined, making it increase mana costs, making it a transitional item for mid-lategame, unless you choose to combine it early for burst of ap at the cost of sustain)
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100 AP
10% CDR
Unique Passive: Whenever you deal spell damage gain mana equal to 2% of the damage dealt.
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100 AP 10% CDR 15 Magic Penetration. Unique Passive: Whenever your health reaches critical levels, gain a shield that absorbs 200 damage for 5 seconds, 45sec cooldown. Unique Passive Lich: After casting a spell, you next damaging spell within 4 seconds heals you over 3 seconds for 30% of the damage it deals, 8 seconds cooldown.
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