It has the following text: If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead
Once this ability gets going the Dragons you create can easily snowball into more Dragons, and from there a victory
TL;DR: If someone tries to draw extra cards, they either end up discarding and drawing, or milling instead, so they never actually go up on cards
I'd wager that having Ultimecia, Temporal ThreatUltimecia, Temporal Threat, Displacer KittenDisplacer Kitten, and Verity CircleVerity Circle on your board simultaneously will allow you to run away with any game easily
If your pods heading too far down the battlecruiser route, you should consider picking this up to remind them that Magic can be a very fast game
That makes Heroic Intervention effects more reliable, but this is card advantage and in Red