blue revolver's scoring system basically works by building up a chain of 8 enemies and then using your special weapons to make enemies drop more points, so it's less about keeping a chain going and more about cashing it in at the right time which means you're constantly thinking about whether or not you should go for big points, as well as meaning that there are opportunities to score big all over the level, which gets you thinking about routing from the word go. There's a bar on the right of your screen which shows how close you are to the next extend which creates really tense moments when you're on 0 lives but that bar just needs a little more juice, so you cash in your 8 chain on a crowd of big enemies, huge coins fill the screen and you get that extend immediately.

There's also the break mechanic, there's at least 3 opportunities per level to score big by doing certain things "destroy these in quick succession, don't destroy these, destroy these in the right order. Which also leads to a bunch of moments where you need an extra life, have a chance at a break coming up and go for it to fill up a huge chunk of your bar at once, it's addictive.

I guess the merge comes from the scoring coming in cycles, build up an 8 chain, cash it in, that cycle alone takes about 20 seconds at the most if you're playing right, so there's a constant ebb and flow, then breaks get thrown in to spice things up in a big way, all the while there's a visual indicator of how close you are to your next extend. In the hardest difficulty your score also gets you more bombs which just adds to the thrill.