Rune cost reduction not reducing air rune cost to zero?

[RaptorSolutions]

I have mystic air staff that reduces air rune cost by 7. I run wind blast which uses 6 air runes and surge 2 which uses 4 air runes, yet every attack still seems to consume 1 air rune.
So what's going on? It can't be that the wiki is outdated right?
I also have the slayer Skull cape and wizard scroll 2 for rune preservation if that somehow interacts.

[BinaryBrain]

According to Update 1.3, Bugfixes, "Fixed Rune Costs being able to go below 1."
https://news.melvoridle.com/upcoming-v1-3-changlog-need-to-knows/

Seems as if zero rune cost is not possible anymore.

[RaptorSolutions]

So sometime in June a couple months back, guess the wiki just isn't updated.
I guess it's fine if the HCCO guide isn't updated, but apparently this one isn't either. https://wiki.melvoridle.com/w/Rune_Cost_Reduction

Thanks. Looks like I'll need to leave it runecrafting a couple hours since I'm not actually doing CO.

[O皿O]

Since the Abyss DLC update, it's not possible to reduce consumption to 0 anymore.