Forum:Pegasus' complaint about Castle of Dragon Souls.

I trust that those of you who are here have seen [this], so my question: when Kaiba uses the effect of Castle of Dragon Souls after using Chaos Emperor Dragon or whatever, Pegasus says that Castle Of Dragon Souls' effect is optional and that Kaiba couldn't use it, what exactly did he mean by that? As far as I can tell, Castle says "when" not "if". SwordoftheSpirit (talk • contribs) 06:24, July 24, 2013 (UTC)