Tar Baes

[Rosenberg]

Hey, so this topic is going to a little vague, so apologies in advance.

I went to a GW tournament a few years ago and someone had a Nurgle army with an amazing tar effect on the bases. I asked the guy how he did it and he showed me that it was just straight from this little bottle, no varnish or anything. Just an amazing, shiny tar effect straight from the bottle. He said that sometimes it became a little jelly like when hot but still stayed on the bases fine. 

Anyway, I've been trying to search for the product but haven't had any luck so thought I'd see if anyone on here knew what I was on about. Any suggestion would be much appreciated. 

Kind regards,

Mikey