AAron,
Windsor and Newton make a fine set of water mixable oils. I would suggest the following: Burnt Umber (Dark Brown), Raw Umber, Burnt Sienna (Reddish Brown), Yellow Ochre, Van *** Brown, Lamp Black. These colors are great for doing dot filters.
The awesome thing about the water mixable oils is that they behave just like acrylics. They are mixable with water, (I use windex) they cure quickly (compared to oils) they are easy to use and they clean up with water.
They are somewhat pricey, around 5.50 a tube but a tube will last you until your children are grown, gone to college, married, have children and their children have children.
I use these paints pretty much exclusively. I cannot give a better endorsement and I don't work for the company either.
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