Who else thinks it awkward that a complete item doesn't retain the passives of the pieces it was built from? Losing the passive on lost chapter feels like I'm being punished for completing Morellonomicon.
SkyblazeHydraX31 votesIt doesn't so much as lose it as the mana passive is changed from levels to kills and assists. Thus it rewards aggressive plays and the burst mages intended to build it are rewarded for participating and playing well, and as levels scale up and come by more slowly the passive remains relevant.
Lost Chapter on the other hand is good for poking and skirmishing early game, when the primary goal is to farm or outplay the opponent and get a level/gold advantage. Look at it this way; by the mid or late game when you're participating in team fights or singling out high-priority targets, would you rather get mana back for casting more spells by getting that lucky level up, or by playing well and helping to secure the kill?
Oakleaf Ranger1 voteswell the reason I don't like is that the champs I build it on don't necessarily get kills early on but prioritize the mana/mana regen along with CDR and AP instead of a larger mana pool from tear or tankiness from ROA
SkyblazeHydraX31 votesPerhaps you should consider changing your build, in that case. With the AP, CDR, and passives, Morellonomicon is intended to be the early game aggro item for mages. If you're not getting kills and assists to make full use of Morellonomicon's mana restore passive, then you will end up feeling like you're being punished for losing Lost Chapter's more passive iteration.
Oakleaf Ranger1 votesWell one of the champions I build Morellonomicon first is Malzahar. I hear people being told to ROA on him but experienced malzahar players don't need/want it since their positioning and understanding of his limits lets allow to take Morellonomicon over ROA. Personally I hate it on him, don't care for a large mama pool from tear, so what else is there then?
SkyblazeHydraX31 votesHonestly, I've built Rod of Ages on him first in the past. But without the scaling CDR glyphs to compensate, I definitely see the benefits to Morellonomicon. Buuuut if you're not feeling Morello's is useful, and you don't feel like Rod of Ages or Tear....
Why not try something for yourself and go with 
Hextech GLP-800? It gives you AP, HP, and mana, but not in the late-game manner of Rod of Ages, and the active would certainly be helpful for escapes or perhaps setting up to land your combo.
....Honestly I'm wondering if I should try it.
Oakleaf Ranger1 votesWell cause I want the CDR... The hex tech items are very niche or gimmicky weak. The only one I see build is the the rocket belt and surprise only on ap burst mages/assassins which malzahar isn't.
SkyblazeHydraX31 votesThe ice gun does damage and the slow, although brief, could be just enough for you to more reliably land a Q and set up your combo.
Oakleaf Ranger1 votesIt's reliable enough already early to mid game, and when champions start building mobility and/or ways to avoid and it starts to become an issue I already have or am about to complete rylias which does the ice guns job much better with similar stats. Plus the damage from the active isn't enough to make me want it
Quepha1 votesWell one of the champions I build Morellonomicon first is Malzahar. I hear people being told to ROA on him but experienced malzahar players don't need/want it since their positioning and understanding of his limits lets allow to take Morellonomicon over ROA. Personally I hate it on him, don't care for a large mama pool from tear, so what else is there then?
Malzahar is great at racking up kills and assists...
Oakleaf Ranger1 votesNot after that last nerf that guy ain't getting any solo kills early on unless the enemy is incredible bad.
Quepha1 votesMorellonomicon as the GW item for AP champs (with a bunch of damage on it!) means that it has this theme as the 'kill secure' item which is why they gave it the mana regen passive on kill to further emphasize this.
Having both regen passives would give a ton of potential power if a champion got a kill and a level-up back-to-back that would probably have to be balanced around so both effects were much weaker.
Leaving the level-up passive in place of the on-kill passive would mean a bunch of gold value on this fully completed item just turns off at some point in the game, which feels really bad for players who build the item.
Oakleaf Ranger1 votesWell in MALZAHAR case he just needs to be able to get over the laning phase now so by item 2-3 he is pumping out respectable damage without worrying about mana at that point idk about other champs who face a similar dilemma about wanting to build Morellonomicon but want the last chapter passive