Witchwarper InfiniWorlds; action type, and can you spend more slots than 1?

[Zwordsman]

Howdy

So.. Fairly certain I know the answer. But I wanted to double check.
Off hand I'm assuming Infini Worlds is a standard action; as it doesn't state an action in the description I see. Its a SU ability so I asssume standard action yeah?

It states "expand A Witchwarper spell slot of 1st lv or higher" So can you only pay 1 per casting?

So, these two together mean I can't say.. take one standard action to use the ability and pay 1 lv 1 slot and 1 lv 2 slot, to produce an area of effect with constant damage and difficult terrain.
Nor could I spend 3 lv 1 slots to get the effect.

Is that right?

I wanted t o double check as occasional wording makes me think I could. But then I go back and it looks like nope.
As if i could pay more for a faster action economy I'd actually quite enjoy this ability. Or if I could pay RP for it; though thats home brew unless they put out stuff in the next book (alt class !)

Thanks in advanced for helping me fact check my wishful thinking

[Wesrolter]

As a standard action, you can create a bubble of altered reality,
projecting elements of parallel existences into your current
universe.
Yes, it is a standard action.
You expend a witchwarper spell, sounds singular.
From what I have seen, usually spending a spell slot is usually done as a single spell.