AbstractDigital literacy games can be beneficial for children with reading difficulties as a supplement to classroom instruction and an important feature of these games are the instructional supports, such as feedback. To be effective, feedback needs to build on prior instruction and match a learner's level of prior knowledge. However, there is limited research around the relationship between prior knowledge, instruction and feedback in the context of learning games. This paper presents an empirical study exploring the influence of prior knowledge on response to feedback, in two conditions: with or without instruction. Thirty‐six primary children (age 8–11) with reading difficulties participated: each child was assessed for their prior knowledge of two suffix types—noun and adjective suffixes. They subsequently received additional instruction for one suffix type and then played two rounds of a literacy game—one round for each suffix type. Our analysis shows that prior knowledge predicted initial success rates and performance after a verbal hint differently, depending on whether instruction was provided. These results are discussed with regards to learning game feedback design and the impact on different types of knowledge involved in gameplay, as well as other game design elements that might support knowledge building during gameplay. Practitioner notesWhat is already known about this topic Instructional supports, such as elaborative feedback, are a key feature of learning games. To be effective, feedback needs to build on prior instruction and match a learner's level of prior knowledge. Prior knowledge is an important moderator to consider in the context of elaborative feedback. What this paper adds Providing additional instruction (eg, pre‐training) may act as a knowledge enhancer building on children's existing disciplinary expertise, whereas the inclusion of elaborative feedback (eg, a hint) could be seen as a knowledge equaliser enabling children regardless of their prior knowledge to use the pre‐training within their gameplay. Highlights the importance of children's preferred learning strategies within the design of pre‐training and feedback to ensure children are able to use the instructional support provided within the game. Possible implications for pre‐training and feedback design within literacy games, as well as highlighting areas for further research. Implications for practice and/or policy Pre‐training for literacy games should highlight key features of the learning content and explicitly make connections with the target learning objective as well as elaborative feedback. Pre‐training should be combined with different types of in‐game feedback for different types of learners (eg, level of prior knowledge) or depending on the type of knowledge that designers want to build (eg, metalinguistic vs. epilinguistic). Modality, content and timing of the feedback should be considered carefully to match the specific needs of the intended target audience and the interaction between them given the primary goal of the game.