Create a new rectangle using the rectangle tool with the following dimensions and x and y position. Also make sure that you click the "Not Rounded" button on the toolbar before drawing out the rectangle since you do not want it to have rounded corners. Now press F1 and select the rectangle you just made. Then press "page down" once to lower the layer of the rectangle below our traced picture. Now press Ctrl+Alt+Shift to open up the stroke and fill dialogue box and apply the following settings after clicking the fill tab and the selecting the gradient fill button.

 
Now click on the create and edit gradients button.  Zoom out a couple of times from the document by pressing the "-" (minus) key, then place the two small white squares controlling the gradient of the rectangle in the following positions.

If you have reached till this point in the tutorial, you can give yourself a pat on the back cause we are half way there. Once you learn the techniques, you can apply them to a variety of future projects. Let's continue.

We will now use the following picture of blood splatter. You can right click on the picture and click save as on your browser and save it to your hard disk. After that we have to import this picture inside Inkscape. For that, we click on File>Import and then browse to the picture's location, select it and then click open.

Don't worry if the image looks really small here. We will quickly fix that by tracing it and converting it to vector graphics. Then we can scale it to any size we want without losing its image quality. Select the picture of the blood splatter by first pressing F1 and then clicking on it, after that go to Path>Trace Bitmap.

I used the  settings on the left inside the trace bitmap dialogue box. Click update button to get a preview of your settings. I selected a value of 0.580 for Brightness cutoff. You can then select OK to trace the bitmap. Close the trace bitmap window after doing these steps. Click and drag the traced blood layer away from the original picture. Then select and delete the original picture because we won't be using that anymore. Click to select the traced bitmap then assign a blood colour to it by pressing CTRL+SHIFT+F to open up the stroke and fill options.

We do not need a stroke for our blood so click the stroke paint tab and then click the "X" button on the top left. For the fill we use the above settings. Select the blood splatter again and use one of the corner scale handles to scale it to the size of your canvas.

After that with the splatter selected, press the page down button to lower the layer of the blood splatter below the traced artwork of the Warhammer character.