If 嗜血印 Bloody Spell generated the same gross revenue on the Epic Games Store, 艺龙游戏 would keep approximately $15,407,694 - that's $2,878,409 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $1,964,686. Epic charges 0% on the first $1 million in annual per-app revenue and then 12% on the remaining amount. On GOG (30% cut), the developer would earn approximately $12,160,666.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.