For those of us using Mysctraft portals. Do not use wraith lamps in close proximity or the portals will NOT activate. Looks like within the same chunk area. remove the lamp and they'll work again.

This information byte brought to you by RobinHood06, Draze84 and Paragers.

Wrath lamps cause a LOT of issues with multiblock structures or anything that uses air blocks (like a portal or tank) because they modify air blocks to add a light source and what not.