When a monster(s) would be Summoned, OR a Spell/Trap Card is activated: Pay half your LP; negate the Summon or activation, and if you do, destroy that card.
Rulings
Netrep Rulings
“Solemn Judgment” can not be used to negate a Special Summon if that Special Summon occurs as a result of another card effect.
Special Summon monsters like “Dark Necrofear” that have their summons negated by “Solemn Judgment” are not considered properly summoned and may not be Special Summoned from the Graveyard.
Q: If a person uses “Solemn Judgment” and the resulting Life Points results in a decimal, what happens? Does it round up or down? A: If equal or more than 0.5, round up. If less than 0.5, round down. bishop, 01/20/2004