Its cowsay!
What more do you want!
Usage: cowsay "your text here (in quotes)"
pastebin get fFCNNs52 cowsay.lua
Ported from: https://gist.github.com/Gaichu/1c5b63c0093512b72779
You don't even need pictures, here's what it looks like:
HI!
\ ^__^ \ (oo)\_______ (__)\ )\/\ | |----w | || ||