Practical effects artists Tom Woodruff Jr. and Alec Gillis are the mad geniuses behind some of the most terrifying, bizarre, and iconic movie monsters. Woodruff and Gillis, cofounders of Amalgamated Dynamics, have designed creatures and practical effects for science fiction, horror, and fantasy movies for the past 35 years. They built the worms in Tremors (1990), the animals in Jumanji (1995), and even Tim Allen’s fat suit in The Santa Clause (1994).

In the short video above, Great Big Story goes behind the scenes with Woodruff and Gillis at the Amalgamated Dynamics studio. The practical effects wizards show off some of their favorite creations and explain why, in an industry increasingly dominated by CGI, practical effects will always be important.

Banner Image Credit: Great Big Story, YouTube