One of only a few legendary cards I'm aware of that you might have cause to use the Legend rule against yourself.
A fringe case is Flagstones of Trokair, which allows you to play Armageddon effects, siphon land from your deck, and trigger landfall.
An even more fringe case is a 60 card battle of wits deck. You ramp into a Spawnsire of Ulamog, and after you blow his ultimate, you cast a pile of 200 Legendary eldrazi which kill themselves and get shuffled into your deck.
Posted By:
kiseki
(8/11/2011 12:23:22 PM)
@Manji187
Yes, we all know that this is Legendary. The point of Rite of Replication is to gain control of your opponents creatures, not to keep 6 copies of this in play. All 5 token copies from Rite enter at the same time, and all 6 you control die at once, which means you get to steal 6 creatures for 9CMC, which is far better than Plague Wind if you ask me...
Posted By:
MrFluffyThing
(4/26/2012 11:31:17 AM)
Keiga, the tide star + renegade doppleganger + rite of replication kicked = mass mind control
Posted By:
Zalasin
(5/14/2011 10:14:38 AM)
A very dangerous blue flyer that, aside from leaving a parting gift, even has a single blue in its casting cost, making it highly splashable in decks that don't usually feature Control Magic effects. Probably not as popular in his time due to the fact that it wasn't always useful to steal a creature, while 5 life always is.
Posted By:
Equinox523
(5/10/2011 9:52:10 AM)
@Snoopfrogg: Nice suggestion, Twisted Justice becomes a sorcery Mind Control with "Draw 5 cards" attached to it... Not so bad...!
My favourite Kamigawa Dragon for sure, and my favourite non-red Dragon. With Divine Reckoning or Cataclysm it's surely a win/win situation. Its board presence is so heavy that it's almost impossible to your opponent to stay alive without losing card advantage, except some exile effects...
5/5
Posted By:
leomistico
(10/7/2011 5:47:45 AM)
@ MagicShine. The annihilator mechanic triggers as soon as the eldrazi is declared as an attacker, so if you sacrifice Keiga then the attacking creature will come under your control before the damage is dealt. Its attack will not finish.
Posted By:
iHARBiNG3R
(2/11/2013 6:49:21 AM)
Swing with Keiga for 5, Fling Keiga for 5 more, steal your opponent's best critter, protect your junk from the ensuing groin shot. Fun times.
Posted By:
SkaerKrow
(12/1/2011 8:32:31 AM)
The best part? It's indefinite!
No strings attached, like Roil Elemental. No "Until End of Turn" Bull like Conquering Manticore or Zealous Con***s.
It's just "Take control". HELL YEAH!
Posted By:
Ferlord
(10/17/2012 11:55:44 AM)
For only 
more than Mind Control, you get one stapled to a 5/5 flying body. Sure, it only kicks in upon death, but then, how awesome is it when your opponent is too afraid to deal with your flying fattie?
Posted By:
Arachnos
(2/4/2013 11:15:05 PM)
@Land_Comment:
Emrakul, The Aeons Torn only has protection from colored spells. Keiga can absolutely target him.
Posted By:
EndOsiris
(6/15/2011 2:52:01 PM)