This is an articulated Magikarp. It can move its spine and fins. It is a high poly model and can be scaled up to be very big and not lose a lot of quality. 

If you have a single colour printer, Print the red parts 1st at your chosen scale. Then print the other parts at 1%-3% smaller depending on how big you print and the accuracy/tollerance of your printer you may not need to do this.

For multicolour machines using Cura as an example. (untested as I do not own a multi material printer)

Load the parts, set the colour of each part, join them togeather. Then you can scale them as big as youd like.

If you have a 4 material printer you could possibly print the whole thing in one go using a disolvable support.

Infill is needed but only to support the concave sections. eg the eyes slot, mouth and top fin slot. Internal support instead of infill is possible is your slicer supports it.

Support is needed mainly to help the stick parts to the bed. Support only needs to touch the build plate for most parts. But if you print the large, the head and tail frame may need some extra to prevent drooping.

The .rar file containes:

All the parts nessassary to print the magikarp. 

Blender files of when it was being modeled, when it compleded and assemebled and when it was dissassembled ready for a single material printer.

The single material printer files are orinetated to get the best strength and quality possible and minimising support to the underside or where parts are guled togeather.

The photos were printed at 150% scale for the red parts and 147% scale for the white and orange.

0.1mm layer height.

When assembled it is 8cm long.

Hope you like it.

Credits.
Modeled by me buy uses a modified version the the ball joint by ELLINDSEY
http://www.thingiverse.com/thing:584405