How many of each half of the Pokemon LEGEND cards can I have in my 60 card deck? Is it 4 total or 4 of each half?
You can put up to 4 total halves of each Pokemon LEGEND in your deck (e.g. 4 Ho-Oh LEGEND halves and 4 Lugia LEGEND halves), but you cannot put 4 of each half of a Pokemon LEGEND in your deck (e.g. you couldn't have 4 Lugia LEGEND top half and 4 Lugia LEGEND bottom half). (GS:Heart Gold/Soul Silver FAQ; Feb 11, 2010 PUI Rules Team)
Source: HeartGold & SoulSilver FAQ (2010-02-11), PUI Rules Team (2010-02-11)