My thought: I gave enough citations, including from Krishna's mouth and from Arjuna's own, that Shikhandi killed Bheeshma. Not merely helped or aided Arjuna, but killed.
That being said, I don't believe it happened in a vacuum. Shikhandi couldn't defeat Bheeshma on his own as seen on Day 7. Part of the reason is that Bheeshma did have a huge number of guards surrounding him as was appropriate for the commander-in-chief. Part of the reason COULD BE that the old chap was simply better than Shikhandi. Which was probably why Krishna was constantly urging Arjuna to kill even though the oath belonged to Shikhandi. Arjuna COULD kill Bheeshma but wasn't willing.
When the Pandavas, Upapandavas, Abhimanyu (I believe he was also there), and Shikhandi did a combined attack, death became inevitable for Bheeshma. This is where Bheeshma deciding to stop fighting Arjuna becomes important. His bigotry is well-documented in his own words in Anushasana Parva. He definitely did not want to die to a man he considered a woman. Knowing he was going to die, Bheeshma preferred to die at Arjuna's hands instead of Shikhandi's. Bheeshma's own words about Arjuna's arrows piercing his vitals are proof. Arjuna didn't use any of the special astras. Otherwise, arrows are arrows. Similar to bullets, unless one were to dig them out and examine, it wouldn't be possible to tell the difference for the one dying. Also, if he stayed alive for so long after war, he certainly wasn't struck in ANY vitals. He bled to death over days. He preferred to do so instead it being bandied about a gay man brought him down.
Edited by HearMeRoar - 5 years ago