Corvus Glaive - Michael James Shaw
Corvus Glaive is Thanos' right-hand man and first appeared in Avengers: Infinity War. Corvus is played by Michael James Shaw, who was originally auditioning for a role in Black Panther. The casting directors hijacked his audition and placed him in Infinity War. Shaw is basically unrecognizable in the CGI makeup.
Predator - Brian Prince
Predator is one of the most iconic sci-fi franchises ever. There are tons of spin-offs and reboots, including The Predator which features 6 foot 10 inches tall Brian Prince. It was difficult for the casting director to find the perfect match, and Prince came in just at the right moment. He's also a prolific stuntman, which made him the perfect candiate.