what does putting an ern in a bomber do?

[flamewolf393]

So Ive got two runways with 10 bombers each, one of them is all ern'd, the other is normal. They are targeting similar levels of creeper on different parts of the map, and theres no difference in their damage or anything. So what effect is the ern having?

[Grabz]

https://knucklecracker.com/wiki/doku.php?id=cw4:info:ern_crystal