BW is a fun game in its own right to be sure...many just dismiss it as "vector Robotron" but it has its unique aspects as well. For instance, look for a "flashing" bug on each level. If you can kill him and retrieve the "$" before the competing bug gets it, you get a successive point amount starting at 600 points, then 650, then 700, etc. I think it maxes out at 800 points. But if the competing bug gets to a "$" before you do, the point counter resets to 600. So it's like a game within the game

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It also gets MUCH harder than Robotron...my high score is around 500K (starting from level 1 and ending around level 60 or so) and it is simply insane at that point...virtually unsurvivable actually...although I'm sure they're are/were players that are/were better then I.
In answer to some of your questions/observations in the video:
1. The red web lines allow your spider to cross only from out to inner web area, but you cannot cross from inner area to outer.
2. The green web lines allow your spider to cross either direction, but they do not allow the enemy bugs to cross from inner to outer web area. This can be useful to fend off bugs on later levels.
3. The indestructible bug is somewhat useful in that he will destroy any red web lines should he cross them in his pursuit of your spider. So if a red lines is in your way, you can use him to take it out. He can be killed but only if he is the last bug on the screen (at which point he will also try to escape).
Enjoy!
Jon