Section 4B: The Power Plant
The Power Plant is the only optional area in the game.
Technically, Section 3B is also optional, but the Power Plant is the only one where there's just one way to reach it. The only way to get here is by going through Section 3B: Canyon Battle. Going through any of the other routes leads you to Section 4A: The Ruined Highway, where you get to pick your path for the rest of the game, but 3B leads you here with no choice of where to go next. Might as well make the best of it, eh?
It's a fairly tricky area if you're impatient. The main gimmick is that the route is filled with mini-pylons that, every now and then, generate a barrier of electricity. This is the only area in the game this hazard appears! You can drive through it if you want, but it'll drain your energy pretty quickly- time it wrong and you'll lose a whole energy bar making your way through it. Instead, just wait for the electricity to stop, then drive through. Simple as that, really. Of course, the place is also crawling with enemy tanks, mostly Louis and Gustafu units, with the odd Becks Haus showing up too. They can shoot through electric barriers, but you can't unless you use your F meter up, and they can also waltz through them with no problems. Feel free to take your time- it's tempting to rush to pass through some pylons to avoid fighting tanks, but they'll usually switch on before you make it safely past, frying you. There's no rush, this is a long section, and just making it to the tank-infested forest on the outskirts of the power plant doesn't count as a checkpoint. So, y'know, take it slow.
Unlike Section 4A, you have no choice- leaving the power plant takes you to Section 5C: Long Road Ver. C.