(CNN) -- Egyptians swarmed Cairo's Tahrir Square Tuesday, seeking to revive a democratic groundswell that swept the country's former strongman from power nearly two years ago and demand that the man they chose to replace him respect their wishes.
Protesters waved flags and banners, chanting slogans and calling on President Mohamed Morsy to roll back his decree on presidential powers or resign.
"I now know that the Brotherhood does not work for the nation but for themselves only," protester Abu Eita said, according to state-run Nile TV. "Egypt is not all Brotherhood."
At least one protester died in early clashes with authorities ahead of the massive demonstrations planned Tuesday night, the Ministry of Health said. The opposition Popular Alliance Party said the protester died after inhaling excessive amounts of tear gas.
Protesters are angry with Morsy for his declaration last week that his edicts are beyond the reach of judges in what critics call an unprecedented power grab. A statement Monday night that appeared to at least partially limit the scope of the decree did not seem to salve their anger.
On Monday, his office clarified the edict, saying it only applied to "sovereign matters."
Morsy "did not give himself judicial power" but did provide "immunity for his presidential decisions," said Jihad Haddad, a senior adviser in the Freedom and Justice Party.
He added that "the president himself (is) not immune from judicial oversight," though it wasn't clear in what instances that would come into practice, or if there was anything preventing Morsy from issuing a new decree so this could not happen.
Protesters want to show that "the whole population of Egypt is against" Morsy and his backers, said former Finance Minister Samir Radwan.
Morsy and his supporters in the powerful Muslim Brotherhood movement have defended the policy as necessary to defend the fragile Arab Spring revolution that pushed former President Hosni Mubarak from power and led to the country's first free elections.
On Tuesday, the Brotherhood's official Twitter feed dismissed the protests as underwhelming and said what it described as a low turnout indicated a "lack of support among Egyptians."
Video showed a packed Tahrir Square, with protesters clogging the roundabout and tents filling the grassy area in the middle. There were no official crowd estimates.
The Muslim Brotherhood scrapped its own demonstration to show support for Morsy -- also scheduled for Tuesday -- "to avoid any problems due to tension in the political arena," said spokesman Mahmoud Ghozlan. But the Muslim Brotherhood Twitter feed told opponents to brace for "millions in support of the elected prez."
Morsy's Freedom and Justice Party is the political arm of the Muslim Brotherhood, the once-banned Islamist movement.
Morsy's decree Thursday said that judges can't overturn his decisions or interfere with an Islamist-dominated council writing a new constitution.
He also sacked the nation's top prosecutor.
In addition to outbursts on the street, Egypt's judges have reacted. All but seven of Egypt's 34 courts and 90% of its prosecutors went on strike Monday in protest, said Judge Mohamed al-Zind of the Egyptian Judge's Club. He described Morsy's edict as "the most vicious ... attack on the judicial authority's independence."
Morsy insists he's trying to protect Egypt's fragile Arab Spring revolution, not accumulate unchecked power. His moves "cemented the process that would create the institutions that would limit his power, define the constitution and have parliamentary elections so that we can say this is a democracy," said Haddad.
Senior presidential aide Essam El-Erian called concerns about Morsy's edict overblown, blaming the protests on "counterrevolutionary forces" loyal to Mubarak's party. Polls show "an overwhelming majority supporting President Morsy and his decisions," Haddad said Monday.
But that's not how his political foes -- seen as "heretics" by many members of the Muslim Brotherhood, according to Washington Institute for Near East Policy fellow Eric Trager -- look at the situation.
Amr Hamzawy, who'd been in the now-dissolved parliament, said action is needed to prevent more "suffering" under a president with "sweeping powers," as Egypt had for 60 years under men like Mubarak, Anwar Sadat and Gamal Nasser.
"Morsy is the ... president who has sweeping executive (power), sweeping legislative (power) and ... puts himself above the judicial branch of government," said Hamzawy, founder of Egypt's Freedom Party. "That is a very dangerous mix, which can only lead to a dictatorship."
The rest of the world is watching, too.
Former U.S. diplomat Jamie Rubin said Morsy's edict "brings to mind all the fears that people in that part of the world have had about the Muslim Brotherhood when it comes to democracy."
The unrest raises new concerns about stability in Egypt, which has gone through two years of protests and turmoil.
"The majority of the people are really suffering, and they were looking forward to some stability," said Radwan, who served under Mubarak as well as in the government that followed him. "I'm afraid that this constitutional declaration has blown it up."