The Joker adds the final punchline to the series
Seeing the Joker in this series is bringing readers back to reality of how things should work in the world of superheroes. That point was clear when he killed Shrike in the previous issue, and now he's killing off Britain's superheroes with his own style of jokes. Squire takes Shrike's death pretty hard, but hides this in front of others other than Knight in order to take down The Joker. Still, despite the Joker being in this final issue, the series itself still retains the wackiness that has been going on. Characters like Birthday Girl shows up (yes, a super heroine called Birthday Girl). Magic plays an important role that goes back to the very first issue. Even at the end, a dying villain plays one final joke. All and all, it's pretty entertaining.
I really enjoyed Jimmy Broxton's artwork throughout this series. His take on Joker reminds me of the silver age version, except more violent. Even when most of these characters are wearing masks, you can see the emotion in their faces when they take on the Joker's scheme.
My only compliant would be that this is the last issue of this series.
Overall: A great conclusion to the series. Knight and Squire has been a fun series, despite the single story issues until these last two issues. I would love to see a full series with these duo as long as each issue is not a single story. That method is was a huge risk when first starting out.