Spells: Cannot giving less Mana than it should

[kaev]

Cast a spell other than Canni after sitting for a few ticks. Do this severl taimes, Notice how you numeric mana amount drops one or sometimes two med ticks worth of mana MORE than the cost to cast the spell... I find the UI usually shows more mana than I have on my casters, there is a persistent but slightly variable desync between the UI mana display and the mana you actually have. An insta-clickie will also reveal this, click before casting Canni, as the UI always gets at least momentarily resync'd by any spellcast including clickies.

Canni is not giving you less mana than it should, your UI is showing you more mana than you have, which gets briefly resync'd when you cast Canni.