Devastator- added Hook and Long Haul to this guy and some Lego pieces here and there. I say this once and only once: every single piece from all of the robots' components are integrated into the combined form.

 

Menasor- added Brakeneck/Wildrider. Only two Lego pieces were added, so Dragstrip's head was easier to store on the back. Also another thing to take note with these combiners: all of them (except Devastator) use an Energon torso from the 2012 sets to assist in forming the combined mode torso.

 

Bruticus- added Blast Off, no extra pieces were required for him. Oh, and this was my very first attempt at adding a kreon to a combiner.

 

Predaking- added Rampage, no extra pieces were required for him.

 

Abominus- added Blight/Blot, no extra pieces were required.

 

Piranacon- added Seawing. I will be adding Skalor once he is released and I do have a few tricks up my sleeve for that. One Lego piece was required so Tentakill's head could be in the position it's in on the leg.

 

Obsidian- added Skrapnel, two Lego pieces were required to make Bullwark's bug eyes.

 

Superion- added Quickslinger/Slingshot, no extra pieces were required.

 

Defensor- added Groove, one Lego piece was required to make storing Streetwise's head easier.

 

Computron- added Nosecone, no extra pieces were required.

 

To see where this all started: http://www.tfw2005.com/boards/transformers-toy-discussion/976633-adding-kreons-micro-changer-combiners-3.html#post11131974