Activate by paying any multiple of 1000 Life Points. Monsters your opponent controls cannot attack if their ATK is less than or equal to the amount you paid.
Rulings
Individual Card FAQs
Paying Life Points for "Wall of Revealing Light" is a cost.
If "Wall of Revealing Light"'s effect is negated by "Royal Decree" or "Jinzo", and then that card is destroyed, the effect of "Wall of Revealing Light" is re-applied.
The monsters prevented from attacking by "Wall of Revealing Light"'s effect cannot even "declare" an attack.
You can chain "Last Turn" to your activation of "Wall of Revealing Light" as long as "Last Turn"'s conditions are then correct (1000 or less Life Points).
You can activate "Wall of Revealing Light" during the Battle Step after an attack has been declared. If the monster's ATK is lower than the Life Points you paid, the attack stops (does not enter the Damage Step).
Trap|
Continuous