Nostalrius Begins - Quality wow vanilla realm (1.12)

Sometimes for whatever reason I miss the last tick from evocation. Is the lag causing this? Whats up with this?

It's not a bug, you just need to time your evocation correctly with your mana regen ticks.

Get an addon that tracks when you get your mana ticks (CT_Tickmod). This should enable you to time your evocation just before a mana tick and will help you to never miss your full 4-tick evocations.

ohh really, did not realize that. Thank you for your help. Much appreciated.