see basically there are a wide range of oxidising agents and reducing agents
for eg
oxidising agents
KMnO4,K2Cr2O7,H2SO4,OsO4 etc
reducing agents
H2/Pd,LAH,NaBH4etc
see some attack only certain bonds others like LAH are highly reactive and reduce all bonds
basically reduction means formation of C-H bond and removal of C-O C-X bonds etc
for eg LAH reduces all double bonds and C=O groups where as MPV reduction ie using Aluminuium isopropoxide reduces selectively only C=O
any doubts you are always welcome to ask!!!!LAH is the strongest reducing agent!!!