[ZeoRangerV]

Tenchi Muyo (the OVAs) actually goes downhill the worst out of all three continuities, mainly because of the 5 year gap between the second and third sets of OVAs. When OVA 3 did suddenly come around the plot had become so up its own ass that you needed a flow chart just to work out what on Earth was going on (not to mention all the crap they pulled with Tenchi's mother).

Daughter of Darkness isn't a great movie either because its set in its own weird psuedo-continuity.

The Tenchi Continuities go:
Main
OVA 1
OVA 2
OVA 3
Tenchi Muyo! GXP
Tenchi Muyo War on Geminar

Hasegawa Continuity
OVA 1
Mihoshi Special
Daugher of Darkness

TV Continuity 1
Tenchi Universe
Tenchi in Love
Tenchi in Love 2 (or Tenchi Forever)

TV Continuity 2
Tenchi in Tokyo

Then there's the 3 Sasami Magical Girl universes too, which the last one having almost nothing in common other than Sasami, Washu and Ryo-Ohki.