Blow open tower door was a mission in Jak 3. Ashelin Praxis needed to have Cyber Errol taken out, but to do so they first would have to punch through the door blocking the way to the Metal Head tower in the Metal Head city section. Torn would drive a cargo transport filled with explosives, while Sig and Jinx were in the HellCat cruiser behind him as escorts. Jak's mission was to use the turret on the cruiser to shoot down any enemies that attempted to strike at the two vehicles.
An on-rails shooter mission through the entirety of Haven City, starting from New Haven and going through the Slums, Industrial Section, the Port and ending at the top of the Metal Head city section. You will be attacked by numerous grunts, wasps, roboguards, sentinels, some blast bots as well as a bunch of missiles from a missile launcher. There are also explosive barrels spread throughout the city, which can be shot to kill any nearby enemies.
The grunts' main tactic is to jump from above onto Torn's or your vehicle, while the wasps and sentinels just come flying in and try to shoot you. The roboguards are the main danger as they can sometimes shoot Torn before you can get a good hit on them, the blast bots on the other hand often enough won't get a hit on either of you and are still big enough to make an easy target. Lastly the missiles; they will appear out of nowhere at specific intervals but you should have enough time to shoot them down.
This mission entirely comes down on reflexes and reaction time, as long as you can move the reticule around fast enough to kill the enemies as they gun or attack Torn you should be doing okay. It remains a difficult mission ultimately, although checkpoints are plentiful. When you destroy the tower door it immediately moves on onto the next mission: "Destroy Metal Head tower".