Thank you for taking the time to play my game and leaving a comment.
I agree that an after-turn report, and knowledge of the opponent's available actions is needed for the body part targeting to have any meaningful impact: at the moment, it's one-way in that only the player knows what actions they lose access to once their body part is broken. Funnily enough, I only considered these elements after playing your game, which worked in these types of elements quite nicely (once again - great work!).
During the initial concept, I did consider having one body part be the critical part (chest for Mech; head for the Kaiju), but I was concerned that the strategy would simply devolve into "Be the first to eliminate the critical part". I also wanted to give the player a chance to keep fighting regardless of the loss of that body part, which is why there's an overall health bar and thr option to attack already broken parts for extra damage.
Amusingly, in replying to your feedback, a new idea popped into my head (unless this is what you meant by "critical part", in which case I've only just understood what you meant): once the critical part is broken, the core of that character is exposed - once the core is broken, then that character is dead. This still allows the character to fight back despite losing the critical part, but now they have a new loss condition imposed on them (either deplete main overall health, have all subsystems destroyed, or have their core exposed and then destroyed)
There's still much to work on, and your feedback has given me a new venue to consider and explore - Thanks again!