To settle his party's nerves, the Labour leader needs another trump card.
Labour's deputy leader's all-out assault on the Lib Dems' record showed that she believes the party can't afford to go soft on the yellows.
The Labour leader pressed Cameron on trade sanctions after a No. 10 document appeared to rule them out.
By forcing Cameron to reaffirm his green credentials, the Labour leader skillfully drove a wedge between the PM and his party.
The PM's loose rhetoric handed Miliband a win as he challenged plans to make 550 Environment Agency Staff redundant.
The coalition made the Labour leader's point for him as it fielded an entirely male frontbench.
The Labour leader broke with his new sober style and hammered Cameron over his refusal to rule out cutting the top tax rate again.
The Labour leader had no convincing riposte to Cameron's claim that he was "an arsonist" who "complains that the fire brigade aren't putting the fires out fast enough".
The "truce" between the two leaders lasted just a week as Cameron declared that Miliband had "all the moral authority of the Reverend Flowers".
The PM's warning that means-testing pensioner benefits would raise only "a very small amount of money" was the most notable moment in a sombre session.