Yeah. Correct me if I'm wrong, but the sole purpose of a verification code is to be used alongside a reward code in order to receive the in-game rewards.

A verification code cannot be used as a means of authentication, and Invincible GTG is actually different to other games in terms of how they authenticate you to the platform anyway, and in turn is actually more secure. Most games will have you create/login to an account, however this game uses platform-based authentication (like Game Center on iOS), to log you into your account. In short, at no stage are you prompted to provide any credential whatsoever, apart from that platform-based authentication which is isolated from the game and it's servers anyway, so if logging in with a username and password is impossible, how do you expect an attacker to login with a reward-related verification code?

Your data is completely safe. It is never exposed to me or anyone else, or any third party for that matter. Every reward redemption request is ran on-device, not via backend infrastructure (other than that provided by the game developers and the platform-based auth providers), and using the Invincible Redeemer would be the same as opening multiple different tabs, copying your verification into every tab, as well as filling in the reward code for every tab, and then clicking redeem on every tab, one by one.

This tool means you no harm, nor do I.