EXCLUSIVE

Ex-WWE Superstar Goldberg has a new pet more terrifying than Stone Cold ... more destructive than Hulk Hogan.

Goatberg has issues. He's peed all over the floor and munched on ritz crackers ... without invitation. Short story ... the goat's a terror, but the Goldberg's couldn't be more in love.

Bill Goldberg tells TMZ ... his wife is a huge animal lover and when he found out her horse trainer was trying to unload the goat -- he took it off the guys hands.

Goldberg says they have plenty of room on their 30-acre property near San Diego ... but the goat is kind of a house pet.

Although the goat is free to chill he actually makes the floors warmer. Moments after this photo was snapped -- the goat went #1 on his wood floor.