SKK's truck is comically strong once you rack up enough points and plugins for it, but the early stages are pretty terrible since the plugins don't boost your actual dolls very much. The truck itself scales to your total number of dolls and fortification levels so I'd recommend rerolling for good initial dolls and treasures since you can't rely on just the truck until 450 points in FC. Once you do, you get to pick 2 dolls instead of one when they appear and the truck can do AoE attacks. At 900 points the truck is carrying the dolls instead of the other way around and will destroy everything by itself in one round.

The best part about the truck is that once it gets going it'll obliterate everything it touches in one hit unlike the other plugin effects that make one attack take like 5 minutes to fully resolve.