Powering a Heavy Core Increases Weight of Nearby Things

Powering a placed-down heavy core with redstone should increase the "weight" of things in a nearby radius (maybe 10 blocks). This would mean that weapon attack speeds decrease, walking speed decreases, and gravity increases. For entities, the increase in "weight" would be affected by the amount of armor that they're wearing.

This would be useful when dealing with heavily armored enemies and players. It would encourage combat revolving around strategy rather than combat focusing on stats. Because it would be difficult to power a core mid-battle, it would be better as a planned defense for a base and such.

This would also have an effect on water and lava speed, allowing pools to be cleared more quickly.

Additionally, it would be useful in mechanisms that use downward bubble elevators, as items would be heavier and thus faster.