Bundled pipebombs

[Berrik]

Roll of wire + 6 pipe bombs + multitool + remote signaller/timer/whatever. Explodes with the combined force of all six pipe bombs at once, but can't be put in a container.

[Weavel]

Definitely a cool idea, but it's so easy to make pipebombs it might overshadow Transfer bombs. I think combining a max of 2 might be ok?

[RAWK_LAWBSTAR]

I don't really see a point to this unless you add in a bit more oompf to it, like making a weaker bomb that tosses the others around it so they detonate a moment later.

Of course if this were a thing it'd need be to be pain in the ass to make and it'd be fragile. Get knocked down while you're carrying one of these around and it might go off in your backpack.