This power took less revision than Divination, and it’s meant to represent one of the core concepts of one-to-one energy consumption (equivalent exchange). Sponsorship originally appeared when I began discussing player powers and rules mechanics, and has only changed in the expanded text:

Original:
“Commit 1 Resource to sponsor 1 Resource for your Reserve. (You may not have more than 5 cards in your Reserve at any time.)

Revised:
“Commit 1 Resource to sponsor 1 Resource for your Reserve. (If at any time you have more than five cards in Reserve, instantly exhaust cards until you have five remaining.)

You can see I changed the expanded wording to become an “if” statement, and I used a word that will appear later in the rules, “instantly.” This is important for timing purposes. Magic: the Gathering and Dungeons & Dragons will use the word “immediately” to denote when something happens (or should happen), and the word “instant” in this case denotes a specific amount of action time.

The greater implication is that the action of exhausting “too many cards” from your Reserve can be modified or somehow interrupted, much as other actions can be modified or interrupted in Magic or D&D. “Sponsor,” as previously mentioned, is used to refer to when a Resource is put into Reserve, specifically by this method, and so effects that look for when a card is “sponsored” will check for this event.

I reused the term “exhaust” from the Development rule for consistency. I created a design rule at this point that the number of cards in Reserve may never be increased beyond five. This is intentionally to prevent the game from becoming more numerically complex than it needs to be. Five is a nice, round number — it might not be an even number, but five is certainly an easy number to remember. *smiles*