Mage Mana Costs
Part of the midseason update is a shift from mana regen to flat mana. Morellonomicon, Rod of Ages and Tear of the Goddess are intended to serve as the means for a mage to get his/her mana.
Morellonomicon will give 400 mana.
Tear and Seraph's will still give 1000 mana, and will refund 25% of mana spent
Rod of Ages will give 300 mana immediately, and stack up to 400 mana.
Now let's look at mana costs and base mana on a few different champions. Stats are assuming level 18.
1091 mana. 19.6 mp5.
Q - 100 W - 110 E - 120 R - 100
947 mana. 14.9 mp5.
Q - 110 W - 40 E - 0 R - 125
1130 mana. 16.2 mp5.
Q - 90 W - 70 E - 80 R - 100
1184 mana. 19.6 mp5.
Q - 85 W - 50 E - 85 R - 80
1090 mana. 19.6 mp5.
Q - 60 W - 70 E - 70 R - 100
1200 mana. 19.6 mp5.
Q - 100 W - 40 per second E - 60 R - 100
1184 mana. 19.6 mp5.
Q - 80 W - 110 E - 20 R - 100
1006 mana. 16.1 mp5.
Q - 60 W - 80 E - 55 R - 100
200 energy. 50 energy regen.
Q - 55 W - 20 E - 50 R - 0
1246 mana. 19.6 mp5.
Q - 120 W - 70 E - 90 R - 60 per second
Most champions, especially the older ones, have mana costs averaging around 80-100 and a base around 1000. That means they start out with 10 casts. With Morellonomicon, that's ~4 extra spells, and Rod of Ages gives 4 as well. Tear gives 1000 extra mana and refunds 25% of mana spent. That means 20 spells combined with base mana, with enough refunded mana to cast 5 more, which will refund enough mana for 1 more spell. Unless you build a Tear, the most spells you're going to be casting is 14. With both Tear and Morello, you get a about 31 spell casts.
So I have a question for you Riot, Xypherous in particular. Is the midseason update intended to make Tear of the Goddess a core item on all mages, and if not, what are you going to do to make Morellonomicon/Rod of Ages an adequate source of mana for champions that can't properly use Tear?