In a campaign I'm running, I'm wanting to send a Revenant (MM p. 259) - or a few - after the party. It's of an Orc War Chief (MM p. 246) that they killed after they entered an Orc camp and killed everyone.

In 5th Edition, is there a template for Revenants that I can apply to a base Orc War Chief stat block, or do I just use the default Revenant stat block in the Monster Manual and say it looks like the War Chief?

Originally I was going to just apply the Zombie template to the Orc, but I think a Revenant works much better for my purposes.