Cost and ability power increased.
Pushing Lost Chapter somewhat later in the laning phase means that its users will get fewer procs of its level-up effect, decreasing overall access to mana.
COST :  ⇒ 1300 gold
| BUILD PATH :
||Amplifying Tome + Sapphire Crystal +
||Amplifying Tome + 80 gold
ABILITY POWER :  ⇒ 40
Lost Chapter, with its mana restore, is a nice item for mages who want to sustain in lane, which makes it a good starting point for most mid laners. As such, one of the first choices we want mages to be able to make is what item to build out of Lost Chapter. Lost Chapter builds into three items now: Luden's Echo, Hextech GLP-800, and Archangel's Staff. More on each of those below.
(Catalyst of Aeons and its upgrades remain good items for the laner who wants to sustain in lane, trading cooldown reduction for health).
TOTAL COST :  ⇒ 1100 gold
UNIQUE PASSIVE Haste: 10% cooldown reduction
Restores mana on level up.
With Morellonomicon emerging as the go-to kill pressure item (spoilers!), Forbidden Idol’s safe regen no longer belongs its build path. We’re pulling Lost Chapter out of the Black Market as a component item for champions like LeBlanc who are in lane to net early kills, offering timed bursts of massive sustain to set up a full spell rotation or two.
TOTAL COST : 900 gold
BUILD PATH : Amplifying Tome + Sapphire Crystal + 115 gold
ABILITY POWER : 25
MANA : 300
MANA INFUSION : UNIQUE Passive - Restores 20% of your maximum mana over 3 seconds upon leveling up
2015-07-30: (Black Market Brawlers release)
Added to the game.
TOTAL COST : 1800 gold
BUILD PATH : Fiendish Codex + Forbidden Idol + 380 gold
ABILITY POWER : 50
MANA REGEN : +100% Base Mana Regen
COOLDOWN REDUCTION : UNIQUE Passive - 20% cooldown reduction.