just for fun, let's see what information we can gather here
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04/02/2011 - Restless - 60M+ XP - went to True Soldiers (Phyrexia)
28/09/2010 - ROTTK - 32M+ XP - left the game (Taliesin)
28/05/2010 - Nognof Brotherhood - 28.M+ XP - self kick (tymm)
28/05/2010 - Sigma Stars- 28.246k XP - self kick (dragon4576)
26/05/2010 - Nognof Brotherhood - 17.268k XP - retired (Sonneillon)
16/05/2010 - Nognof Brotherhood - 16.535k XP - retired (Barr)
16/05/2010 - ROTTK - 16.5k XP - retired (ecofrog)
30/03/2010 - Nognof Brotherhood - 15.578k XP - inactive (vietxchaoz)
26/01/2010 - Nognof Brotherhood - 12.768k XP - inactive (Tazed)
22/01/2010 - Nognof Brotherhood - 12.651k XP - retired (Raist)
29/11/2009 - Nognof Brotherhood - 11M+ XP - self kick (MyDestiny)
18/11/2009 - Nognof Brotherhood - 8.370 XP - inactive player (Cheeese)
25/10/2009 - ROTTK - 7.802k XP - bored player (Tarsis)
22/09/2009 - Red Cell - 5.369k XP - inactive player (Kellyn)
03/09/2009 - Nognof Brotherhood - 4.196k XP - inactive player (Tanto)
30/08/2009 - Nognof Brotherhood - 4.1M+ XP - inactive player (Acheron)
31/07/2009 - ROTTK - 3.865k XP - retired player (Burns)
23/07/2009 - Nognof Brotherhood - 3.429k XP - retired player (Slovenia)
11/07/2009 - Nognof Brotherhood - 3.124k XP - retired player (anthon13)
28/06/2009 - Nognof Brotherhood - 3.068k XP - retired player (Js3b)
19/06/2009 - Nognof Brotherhood - 2.5M+ XP - retired player (tokooll)
25/05/2009 - Nognof Brotherhood - 1.876k XP - inactive player (MARINE)
22/05/2009 - Nognof Brotherhood - 1.400k+ XP - not efficient player enough (Jogge) -- CAME BACK
18/05/2009 - Nognof Brotherhood - 1.281k XP - inactive player (EvilParrot)
10/05/2009 - Nognof Brotherhood - 950k+ XP - inactive player (Darjin)
(I'll update this list as long as new info (bigger XP contributor than the previous one on the list) arrive)