Why didn't Bhishma Pitamaha Amba help

Does Krishna advise Arjuna in Mahabharata to use Shikhandi as a protective shield against Bhishma?

Arjun had Krishna for his charioteer and Hanumanji on his banner. Then why did he need a shield, least of all shikhandin, as a shield? It can be remembered that on the 9th day, Arjun prevented Krishna from killing Bhishma. If he wanted to use Shikhandin as a shield, he might as well have had Krishna kill Bhishma on the 9th day of the battle. Both options were disastrous as they would send a message to the Kauravas that Arjun was afraid of Bhishma and was struck down by his power. It would also have sent the message that Arjun had little faith. That would have encouraged the Kauravas (even after Bhishma's death) to launch a comprehensive attack on Arjun. Don't forget that the Kauravas had a star-studded line-up, even without Bhishma, and Bhisma's fall would get Karna into the action. Instead, from days 11 to 13, we see the Drona-Karna duo on their hindfoot. They wanted Arjun to be removed from the battlefield in order to conquer Yudhisthir. They were not ready to take on Arjun, as Bhishma did with great success for the first nine days.

Of course, Bhishma's success for the first nine days was due in part to Arjun's unwillingness to kill his grandfather. But Bhishma's savage attack on the 9th day changed Arjun's mindset and his professional reputation as a warrior was in tatters. So Arjun decided to take remedial action on day 10. His goals for day 10 were (i) kill Bhishma (ii) undo the damage to the morale of the Pandava Army (iii) severely and irreparably damage the morale of Kauravas through aggression and psycho-operations (iv) the damage to one's own Undo professional reputation and inspire awe in Kauravas

When the Pandavas and Sri Krishna met Bhishma on the night of the 9th day, Bhishma suggested that he could not be defeated because of his "Iccha mrityu" begon, which Arjun had suggested for "Shikandin as a shield". This was a Psycho Ops against Arjun to help Yudhishthir and the Pandavas.

Arjun saw Bhishma's trick for what it was and decided against using Shikhandin as a shield. Instead, Shikhandin moved into his own chariot and Arjun's chariot followed Shikhandin and protected him. Arjun has always viewed Bhishma as a role model since childhood (in fact, he could be considered Bhishma version 2.0). Arjun imitated the example of his famous grandfather from the 9th day in the professional soldier.

Arjun unleashed unprecedented aggression not seen by him in the first 9 days and broke through the Kaurava formation so that he and Shikhandin reached Bhishma. He aroused so much awe in Dronacharya that the latter decided not to stop Arjun and advised Ashwatthama against it. In fact, Arjun's offensive caused various supportive warriors and kings to abandon Bhishma, and only Dusshasana offered decent resistance before being defeated by Arjun

A simple reading of chapter 119 of Bhishma Parva of Mahabharata shows the following : Arjun rightly read the blessing "Iccha mrityu" correctly, since it no longer bestowed Bhishma on the moment of his death. ** He had decided that after cutting off Bhishma's bow he would not attempt powerful shots on Bhishma's armor as this would give Bhishma precious seconds to pick up a new bow, string it, and fire again to neutralize Arjun's arrows . Instead, Arjun just shot Bhishma bow by bow without letting Bhishma shoot a single arrow, and decided to wait for the right moment to launch his mighty blows at vulnerable points on Bhishma's armor. **** Bhishma then hurled fearsome Shaktis at Arjun, who he cut into pieces with his arrows. Then Bhishma again picked up the bow to shoot Arjun, and again Arjun cut bow by bow without Bhishma firing a single arrow. Bhishma realized that "Iccha mrityu" blessings did not imply immunity from the current situation he was in.

A determined arjun cut off his bows without being able to shoot a single arrow.This was humiliating to a legendary archer like Bhishma.He chose to withdraw from the fight and be knocked down by Arjun instead of standing and having his bows cut off without being able to shoot a single arrow.

Lord Krishna had said in the Bhagavad Gita that "Apakeerti marnat atirichyate" (shame worse than defeat) for an excellent man. Bhishma's predicament was just that. He was unable to draw a bow or shoot an arrow because Arjun would not allow him !! He decided to bow honorably (pun intended). He withdrew from the fight and his decision was welcomed by the Rishis, Gandharvas, and Heavenly Ones. A cool breeze blew across the battlefield, followed by a shower of nectarine. Then Arjun, who had spent his time patiently slicing arch after arch of Bhishma in rapid succession, released mighty blows on Bhishma's armor at vulnerable points. He shot 125 arrows that struck and hurt like lightning. Bhishma turned to Dusshasana and praised these arrows, saying they were from Arjun and not from Shikhandin. More arrow strokes followed from Arjun and Bhishma fell upside down and his body did not touch the ground as Arjun's arrows pierced him everywhere with no two fingers between two arrows.

The fight that Arjun waged with so much aggression was in itself a pyscho-op that destroyed the morale of the Kaurava army. Arjun didn't stop there. When Bhishma said to him, "Twam hi shakto maheshwasa datum aapo yatha vidhi" ('O mighty archer, you alone can give me the divine water that I seek by the correct method), Arjun got on his wagon, harnessed his gandiva and turned it up to its twang swung along in all quarters. It was a way of saying to the Kauravas, "Look, you sore loser. See how I humiliated and knocked down your C-in-C who is a legendary warrior. Even so, he begs me (his enemy) for." Water, since you are worthless and good for nothing. I use my fearsome bow to give him water today. From tomorrow these arrows will drink your blood. "Then he circled the fallen legendary archer and man of the with his chariot (parikrama) Bhishma learning and called Parjanyaastra and shot it near Bhisma's head and brought Ganges and quenched his thirst. Note that Bhishmaparva is also the Parva of the Bhagavad Gita, or the store of knowledge. Bhishma was felled by a warrior who was in the same league as himself as an archer and a man of wisdom and learning

From this episode of Arjun who felled Bhishma, the famous Hindi phrase "Acche achhon ko paani pilaana" originated.

The Kaurav Army was always on its backfoot from day 11. Drona wanted Arjun to be away from the battlefield to catch Yudhishthir. The cowardly murder of Abhimanyu signaled to Arjun that Kauravas were sacred to him. He vowed to kill Jayadrath and force Kauravas even more to the hindfoot. On the 14th day when Arjun went after Jayadrath, the Kauarava Army lost 8 of their 11 Akshuhinis (Dvisions) and 7 of them to Arjun alone. Many great Maharathis stood in line to defend Jaydrath and were killed. About 30 brothers of Duryodhna were killed by Bhima on the 14th day!

** The following points emerge: ** 1) Bhishma did not do any match-fixing with Arjun & Krishn. He didn't drop any weapons when he saw Shikhandin. He did not attack Shikhandin, but he fought all the other Pandava warriors, including Arjun. 2) Bhishma continued to fight Arjun until he ran out of ammunition (bows) / until his strength failed and he then only withdrew from the fight. 3) Arjun did nothing cowardice. If he had, the star-studded Kaurava Army would not have been on their backs against him on days 11-18. 4) To say that Arjun used Shikhandin as a shield is wrong and offends Arjun, SriKrishna and Hanumanji Bhishma and Arjun. Bhishma, bow down. Arjun, bow down.