"Question about Hail Caesar Rules" Topic

I have a very large 15mm Vikings and Saxon armies. They are based four figures to a base. I am wanting to do large army battles. I downloaded Hail Ceasar Shield Wall. This is what I want to use for that period. I also have a 15mm Roman and Carthaginian army. I have been using Hail Ceasar Epic rules for it.

My question is this:

Do I need to buy Hail Ceasar for the basic rules to play shield wall or does the Epic have all the basic rules that I need?

Thanks!

Shield Wall is only a supplement, you need HC. Here 's a review:

link

I understand it is a supplement. I was just asking is the basic rules found in Epic the same as the basic rules in Hail Ceasar. I have the Hail Ceasar Epic. Can I use it or do I need to buy the Hail Ceasar rules.

You should be fine using the Epic HC with Viking/Saxons. I assume that you are using army lists from Shield Wall.

The only rule difference I'm aware of is how small units are defined. In Epic, small is 2 bases and standard is 3 bases. In HC, small is 2 bases (80mm) and standard is 4 bases (160mm). (I suspect they changed the rules to match the Epic sprues.) It makes a huge difference for how small Roman units play. However, Viking/Saxon will mostly be standard sized units with a minority of small skirmish or light cavalry units.

Edit: This post has an image from the rule book on unit sizes. Playing 15mm, you'll be more interested in the ratios rather than the actual mm.
link

Thanks!