Arcane Disruption (4e Trap)
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Magical Runes are drawn onto the floor. If the party sees it they may make an Arcana check DC 20 to identify its effects.
The trap's trigger squares are typically 2 x 2. Use it in a bottleneck with an alternate channel. A spellcasting character must then decide if they want to risk using their powers on the magic rune, or to take the alternate path (which may have its own difficulties).
Arcane DisruptionLevel 1 Trap
|Detect: Perception DC 8||Initiative: —|
|♦ Attack(Arcane) ♦ At-Will|
|Attack: (Immediate Interrupt)|
|Trigger: A creature uses an arcane attack power while occupying a trigger square.|
|Effect: The triggering creature is also considered to be an additional target of the triggering power.|
|♦Disable: Arcana DC 19. First Success: Triggering creatures gain a +2 bonus to defenses against the triggering attack. Second Success: The trap is disabled.|