Ouch...

Anyway, here are two cards I made for the Archfiends. I'm not entirely sure of them though, but I'll leave them up for critique. 

1. Der Hölleschach
 Card Type: 
Continuous Spell 
Card Card Effect: You can activate this card if Pandemonium is on the field, and this card cannot he destroyed while Pandemonium is on the field. The following monsters can use these respective effects once per turn by paying life points equal to x200 the selected monsters' levels. 
-Vilepawn Archfiend: You can tribute this card to special summon another Archfiend monster listed here from your hand or deck. 
-Desrook Archfiend: You can move this card to a different column, and if it has no monster in front of it, it can attack your opponent directly.
 -Shadowknight Archfiend: This card can destroy one spell or trap card on your opponent's side of the field if the selected card is in column to the left or right of this card. 
-Darkbishop Archfiend: If this card is diagonal to an opponent's monster, you can destroy it and inflict damage equal to its attack. This card cannot attack this turn, and cannot use this effect until your second turn after its activation. 
-Infernalqueen Archfiend: This card can use its ability of increasing attack once more during the main phase.
 -Terrorking Archfiend: A monster that attack this card or is attacked by it loses half its attack points if it is not directly in front of this card. 
-Checkmate: A Terrorking Archfiend can gain attack equal to that of the tributed monster for the remainder of this turn.   

2. Infernal Pawn Movement 
Card Type: Continous Spell 
Card Effect: Once per turn, you can select monsters on your side of the field listed on "Der Hölleschach" and change their locations. This card cannot be destroyed while "Der Hölleschach" is on the field.

Obviously they're meant to make the "Chess fiends" play a little more like Chess by focusing on positioning.