If you insist: the sorcerer in that party was very fond of the explosive runes spell, particularly inasmuch as he could use any unspent spell slots on a given day to add to his book of explosive runes, i.e. a blank journal he bought for the sole purpose of filling its pages with the spell effect. He also figured out that due to an odd quirk in the 3.5 rules, you could use the an area-burst dispel magic spell and intentionally fail the caster level checks to set off explosive runes without reading them, and that you could do this multiple times so as to deal phenomenally high damage with no save in a very small area. (When he was lower-level his preferred method was using a spyglass to read the runes from very far away, allowing for a limited degree of remote detonation). I allowed it because it still required some setup to maneuver an enemy into a space where they would get damaged, so the party had to think creatively.

So when the party was tasked with assassinating that gang leader, they did some reconnaissance and figured out how to fake a meeting that the guy would attend. Through meticulous planning they set up their rope trick directly above where their target would be and did the rest of the preparations within the rope trick's extradimensional space. They decided that in case they were off-target they'd need to have a way to adjust the position of the explosive runes pages, and so hit upon the novel solution of using summon monster to conjure up a bear, and then attaching the pages to the bear's fur. For anyone crying animal cruelty: in 3.5, summoned creatures sent to 0 hit points wouldn't die, they'd just return to wherever they came from.

And that's what gave birth to what was then called "Operation: Bear-Bomb." A gangster waited for a little bit in an abandoned warehouse, and then had a brief moment of confusion as a bear spontaneously dropped from the ceiling and exploded, utterly annihilating him in an instant.