I'm wondering how to lock-on the TAC cannon. I just got it on the lvl where u fight the big alien think on the aircrfaft carrier but it says "No Target Locked" nad wont shoot! heeeelp!!

I beleive it's a bug. Not sure how to fix it. I'm sure someone else on this forum can help

you have to kill exo alien by normal weapons, and after that, you have to kill big carrier ship by nuke cannon =)

Use the binoculars ( default key: B) for that ^^

thanks!

Few days ago i had a problem with TAC too - when i was trying to kill the final boss, i blew it's hatch open and fired TAC. And guess what. Nothing. I stood there firing continous TAC's (it didn't even want me to lock on), but he just stood there.
Last Crysis mission is way too buggy.

The last two missions can be like pulling teeth compared to the rest of the game. It's as if as the game gets closer to the final levels the sandbox gets smaller and smaller. I'm not sure if that was a design choice but I generally dislike the final two missions except for the interior carrier parts. Plus, the cliffhanger kind of irked me.