Theory: Why did Tywin send Gregor and Amory.

[Kandrax]

This theory can't be proven or disproven, because all three are dead. As we know Lorch and Gregor killed Rhaenys and Aegon(or some another child, if you believe that Aegon is real thing).

But are they first children they killed?

Nope. According to SSM, there is rumour that Amory killed last Tarbeck lord by throwing him into well. And how old was he? Three, like Rhaenys.

Now, let's move on the Mountain. From one Ned's chapter we learn that there is rumour that Gregor killed his sister. Although her age was never told, i believe that she was baby like Aegon.

This rumours without any doubt reached Tywin's ears. So here is why he did send them. He sent them because he knew that they wouldn't hestitate to kill a child.

[Leo of House Cartel]

Yeah, I'd imagine he knew they were the "right kind of wrong".

The whole scenario with Loch and Gregor scaling the Walls certainly sounds like the type of thing that would require a good deal of planning, making me think Tywin knew exactly what he was doing.

One could argue that if The Lord of Casterly Rock really just wanted to detain Elia and the Blood Royals, he would have sent smaller, faster men up the walls to quickly get in and secure the captives- sending an eight foot tall man and a burly chap like Loch on a climbing mission in the middle of a battlezone seems like it would be asking for one of them to get shot down by some loyalist. 

I reckon Tywin sent his physically-unsuited-for-the-task men up the wall because he wanted two of his most ruthless killers to do some nasty work.

[Bernie Mac]

Well for a lot of reasons

• Jaime was what he was most worried about, he would have sent his best after him and Aerys
• He also would have needed men to secure the treasury, the small council and other important dignitaries as well as the port and the gates so Aerys can not escape
• to murder children he would of needed men he could trust, that means men directly under him, which rules out much of his 12k who he is not going to know that well
• he is going to need men who are willing to murder children, many of his trusted men would likely refuse
• he is going to need men who are willing to risk the wroth of the Targaryens
• he is going to need men who are capable of scaling the walls of the red keep and being able to kill any guards that are with them

On top of that Tywin is securing an entire city in chaos with thousands of Crown soldiers still in the city. Overall the pool of talent that is right for this job is not that high. 

[John Suburbs]

Well, Tywin pretty much admits to Tyrion that the intent was to kill the Targaryen children:

Quote

"I grant you, it was done too brutally. Elia need not have been harmed at all, that was sheer folly. By herself she was nothing"

"Then why did the Mountain kill her?"

"Because I did not tell him to spare her. I doubt I mentioned her at all."

So, yeah, he would obviously send in the two men who he knows have no compunction about killing children.

[Van Gogh]

On 6/8/2018 at 4:55 AM, Kandrax said:

This theory can't be proven or disproven, because all three are dead. As we know Lorch and Gregor killed Rhaenys and Aegon(or some another child, if you believe that Aegon is real thing).

But are they first children they killed?

Nope. According to SSM, there is rumour that Amory killed last Tarbeck lord by throwing him into well. And how old was he? Three, like Rhaenys.

Now, let's move on the Mountain. From one Ned's chapter we learn that there is rumour that Gregor killed his sister. Although her age was never told, i believe that she was baby like Aegon.

This rumours without any doubt reached Tywin's ears. So here is why he did send them. He sent them because he knew that they wouldn't hestitate to kill a child.

Tywin needed to prove himself to Robert.  He wanted Rhaegar's children dead.

[BRANDON GREYSTARK]

A tool for every job .Tywin was settling his debts , so Elia and her children had to die . For murdering you send murderers .

[Dorian Martell's son]

On 6/8/2018 at 1:55 AM, Kandrax said:

This theory can't be proven or disproven, because all three are dead. As we know Lorch and Gregor killed Rhaenys and Aegon(or some another child, if you believe that Aegon is real thing).

But are they first children they killed?

Nope. According to SSM, there is rumour that Amory killed last Tarbeck lord by throwing him into well. And how old was he? Three, like Rhaenys.

Now, let's move on the Mountain. From one Ned's chapter we learn that there is rumour that Gregor killed his sister. Although her age was never told, i believe that she was baby like Aegon.

This rumours without any doubt reached Tywin's ears. So here is why he did send them. He sent them because he knew that they wouldn't hestitate to kill a child.

He sent them because they would carry out his orders without question or remorse. Tywin tells his son that while Ser Gregor is a monster, men like him serve a purpose