The rapid growth of computer games and increasing user demand make it essential to adopt complementary testing processes to ensure high-quality games. Human testers are of relevant importance when testing complex 3D games. However, the vast and diverse range of game content, human time constraints, and the lack of automated testing support can compromise the overall quality of game products. To address this challenge, we have integrated a scriptless testing approach into the experimental game LabRecruits and the industrial sandbox game Space Engineers, enabling automated exploration of 3D game scenarios. Our solution involves developing custom plugins for both games into the open-source scriptless testing tool TESTAR, utilizing the Intelligent Verification and Validation for Extended Reality-Based Systems (iv4XR) framework. This research demonstrates the potential of an autonomous scriptless agent for exploring 3D game environments. The autonomous agent significantly enhances spatial coverage test effectiveness within 3D games when incorporating intelligent decision-making algorithms.