Fortnite maker Epic Games is going to reward creators if players spend V-bucks before or after visiting that creator’s custom-made Fortnite experience. The change is happening as part of an update announced Wednesday to the engagement-based formula Epic uses to pay Fortnite creators.

Epic first introduced the engagement-based payouts (which it calls “Creator Economy 2.0”) in March. Under the program, Epic pays creators who build experiences for Fortnite from a pool of 40 percent of Fortnite’s net revenues each month. Epic itself is also eligible to receive money from that pool. At launch, two of Epic’s key engagement metrics for payouts were player popularity and player retention, and soon after, the company added a metric that rewards time played.

Here is the specific language about the new metric from Fortnite’s blog post. The language has been updated since we first published this story to clarify when the metric to applies and to note that this new metric is in addition to others already announced. The updates are in bold:

Effective November 1, we are introducing a new metric to the engagement payout formula that rewards creators when individual players spend V-Bucks in Fortnite the full week before or the full week after engaging with their island. This new metric will be in addition to time played and other metrics evaluating player popularity and player retention that we introduced with engagement payouts earlier this year.

So, as an example, if you buy the forthcoming Alan Wake outfit before jumping into Epic’s Alan Wake-themed Fortnite experience, it sounds like that purchase would contribute to Epic’s payouts it receives as part of the Creator Economy 2.0 program. In the blog post, Epic says that the new V-bucks spent metric “enables us to more accurately recognize a creator’s impact on the shared engagement payout pool and the overall growth of the Fortnite economy.”

The new metric goes into effect on November 1st (which just so happens to be a few days after V-bucks get more expensive), and the first payouts that account for it will be sent on December 30th. “Overall, we find that players who are having fun in Fortnite are most likely to spend in Fortnite,” Epic said. “So, for creators, making fun and engaging experiences is the most important driver of long-term creator success.”

The new metric follows Fortnite’s recent UI revamp that pushes creator-made maps with a YouTube-like redesign. In an employee email about the recent layoffs at Epic, CEO Tim Sweeney detailed how the focus on Fortnite creators has changed the economics of its business. While he says Fortnite is growing again, that growth “is driven primarily by creator content with significant revenue sharing,” which he said is “a lower margin business than we had when Fortnite Battle Royale took off and began funding our expansion.” He also noted that time in third-party Fortnite experiences now exceeds time in first-party experiences.

Fortnite is in the midst of its annual Halloween event, and Epic is planning to sell in-game outfits based on spooky characters like Alan Wake, Michael Myers, and Jack Skellington ahead of the holiday.

Update October 18th, 7:40PM ET: Added new language from Epic’s blog post.