S02E13: The Purge
Old George, the original Forever Knight, reclaims his position, and orders the Knights to remove all aliens on Earth.
Previous Episode 
Season 1
Fame
S1E1 / 23 Apr 2010
Duped
S1E2 / 30 Apr 2010
Hit 'Em Where They Live
S1E3 / 07 May 2010
Video Games
S1E4 / 14 May 2010
Escape from Aggregor
S1E5 / 21 May 2010
Too Hot to Handle
S1E6 / 28 May 2010
Andreas' Fault
S1E7 / 04 Jun 2010
Fused
S1E8 / 11 Jun 2010
Hero Time
S1E9 / 18 Jun 2010
Ultimate Aggregor
S1E10 / 10 Oct 2010
Map of Infinity
S1E11 / 10 Oct 2010
Reflected Glory
S1E12 / 15 Oct 2010
Deep
S1E13 / 22 Oct 2010
Where the Magic Happens
S1E14 / 29 Oct 2010
Perplexhahedron
S1E15 / 05 Nov 2010
The Forge of Creation
S1E16 / 12 Nov 2010
Nor Iron Bars a Cage
S1E17 / 19 Nov 2010
The Enemy of My Enemy
S1E18 / 03 Dec 2010
Absolute Power (1)
S1E19 / 10 Dec 2010
Absolute Power (2)
S1E20 / 10 Dec 2010
Season 2
The Transmogrification of Eunice
S2E1 / 04 Feb 2011
Eye of the Beholder
S2E2 / 11 Feb 2011
Viktor: The Spoils
S2E3 / 18 Feb 2011
The Big Story
S2E4 / 04 Mar 2011
Girl Trouble
S2E5 / 11 Mar 2011
Revenge of the Swarm
S2E6 / 18 Mar 2011
The Creature from Beyond
S2E7 / 25 Mar 2011
Basic Training
S2E8 / 01 Apr 2011
It's Not Easy Being Gwen
S2E9 / 08 Apr 2011
Ben 10,000 Returns
S2E10 / 15 Apr 2011
Moon Struck
S2E11 / 22 Apr 2011
Prisoner #775 Is Missing
S2E12 / 29 Apr 2011
The Purge
S2E13 / 16 Sep 2011
Simian Says
S2E14 / 23 Sep 2011
Greetings from Techadon
S2E15 / 30 Sep 2011
The Flame Keeper's Circle
S2E16 / 07 Oct 2011
Double or Nothing
S2E17 / 14 Oct 2011
The Perfect Girlfriend
S2E18 / 21 Oct 2011
The Ultimate Sacrifice
S2E19 / 28 Oct 2011
The Widening Gyre
S2E20 / 04 Nov 2011
The Mother of All Vreedles
S2E21 / 18 Nov 2011
A Knight to Remember
S2E22 / 02 Dec 2011
Solitary Alignment
S2E23 / 09 Dec 2011
Inspector #13
S2E24 / 04 Feb 2012
The Enemy of My Frenemy
S2E25 / 11 Feb 2012
Couples Retreat
S2E26 / 18 Feb 2012
Catch a Falling Star
S2E27 / 25 Feb 2012
The Eggman Cometh
S2E28 / 03 Mar 2012
Night of the Living Nightmare
S2E29 / 10 Mar 2012
The Beginning of the End
S2E30 / 17 Mar 2012
The Ultimate Enemy (1)
S2E31 / 24 Mar 2012
The Ultimate Enemy (2)
S2E32 / 31 Mar 2012
Yuri Lowenthal
Ben Tennyson (voice)
Ashley Johnson
Gwen Tennyson (voice)
Greg Cipes
Kevin Levin (voice)
