Uhh, what? Let me help. Get one more level (44) and you get…
Mind Flay:
135 Mana
261 Damage.
+45% Spell Power.
Holy Fire:
170 Mana.
331 Damage on average.
+59.99% Spell Power to direct damage, +26.65% Spell Power to DoT.
Now apply talents.
Shadow Form (15%)
Darkness (10%)
Shadow Weaving (3% stacking up to 5 times)
Cast a Shadow Word: Pain before Mind Flay.
(261 + [45%SP]) * 1.31 = 342 / 135 = 2.53 DPM
Searing Light (10%)
331 * 1.1 = 364 / 170 = 2.14 DPM.
Explain to me how 2.14 > 2.53?
Let’s be generous and assume you have 100 Spell Power at level 44.
100 * .45 = 45
100 * .8664 = 87
(331 + 87) * 1.1 = 460 / 170 = 2.70 DPM
(261 + 45) * 1.31 = 401 / 135 = 2.97 DPM
Sorry, bud, but Mind Flay is much more mana efficient than Holy Fire. As expected, when I said:
You were clearly not doing so.
It’s mana inefficient, yes, but it is instant, prevents knockback, prevents Inner Fire stacks from being knocked off, and can be cast in Shadow Form.
Psychic Scream is pretty much a mandatory spell for Priests, even if you’re being money-conscious.
Actually, it has plenty of value even without mistakes. It can be used as an additional form of damage reduction. It can be an interrupt. It’s good for PvP.
There’s no reason not to have it.