The real killer on the vastness isn't the mind bLast but the blood vengance. It's so fun to watch the enemy troops kill themselves in hordes I'm tempted to empower my vastness in earth and have it invulnerbility itself...or maybe nature and regen. They just swarm and die by the hundreds.
Of course a demon lord/heliophagus with some slaves could do that to himself with 9 blood researched...nasty thought really. I can se this being ridiculously powerful.