Institute of CelluloseBoard

The beams worked pretty effectively on the tanks and IFVs however the missiles and the grenades less so due to point defense systems found on these vehicles.
As the point defense systems either launched smaller missiles to counter the other missiles or fired a hot laser to disintegrate the projectiles like grenades.
Meanwhile the main battle tanks returned fire at enemy vehicles with hardlight ordinance, and Infantry of course targeted the enemy vehicles with hardlight anti-tank weapons, and coilguns with electromagnetically charged projectiles.

Their own Nano machines were also sent in, primarily to counter enemy Nano machines or at the very least distract them.
Sentinel drones or else so much more resilient to no machines than expected due to electromagnetic shielding and just the shielding in general but of course still was heavily affected.
It also didn't stop the drones from transmitting locations of targets along with enemy Nano machines so they could be targeted.

Meanwhile the city center being devoid of civilians, and also of course the enemy lacking adequate anti-air defenses, and point defense systems that were destroyed and no aircraft, the monsters begin to Target the city center with CAS, especially targeting some of the structures so they would collapse on large concentrations of enemy forces in the city center.
They made use of FTL aircraft missiles, guided bombs, hardlight guns and explosives, and a few other guided munitions you would expect from close air support.
Of course ebbotian air units made sure to warn colombian forces so they don't accidentally walk into a bombing run, and informed them that they would be softening up the enemy for a few minutes.
The palace wasn't targeted that much however if anti-tank weapons and their other defenses were not in the building they were of course targeted by precision weapons from close air support.

Meanwhile the Army changed up its rules of engagements within the rest of the city basically ensuring that they will only target buildings that have enemy small arms fire coming out of them.
And if there were booby traps in them engineer brigades would be designated to disarm them after the battle if there were no enemy infantry in them.

ODST units upon encountering booby traps and whatnot end up deploying small objects which would essentially attract any explosives with a hint of metal in them in order to clear an area in the building.
They would repeat this process going from different floors and rooms ensuring that the magnet was off but then turned it back on when they were trying to attract them.

ODST casualties indeed were sustained and by that some of them were either minorly or Gravely wounded but it depends that shields were meant to withstand certain explosive forces and the same goes with their armor.
Either way typically the demolitions experts of each ODST squads would go ahead in order to properly spot explosive devices and booby traps and then properly get rid of them by getting them prematurely with a gunshot or otherwise.

They would also use their tactical visors or the sentinel drones that they personally had in order to spot explosives and booby traps and disarm or avoid them.
And of course buildings with booby traps were marked by the ODSTs so engineer brigades can clear them of such later.

Meanwhile from the Imperial army itself they would begin a light artillery bombardment on the palace consisting of mortars and light self-prepared artillery, mainly to test the defenses inside the building.

For imperium and olenlian forces that ended up surviving the close air support bombardment in the city center, they would be facing two regular mechanized infantry divisions that were advancing from all sides in the city center along with one tank division, and an armored ODST unit that came with them.
And they would primarily lay down suppressing machine gun fire and artillery bombardment in order to prevent enemy forces that were stuck in the city center from retreating and from shifting, they made extensive use of towed Photon artillery, coilgun artillery with electromagnetically charged projectiles, electromagnetically charged coilguns that were fired from tanks and IFV's and so on.

Individual squads that were tested with clearing buildings in the abandoned city center primarily used grenade launchers and tossed frag grenades in the buildings, they also made use of tear gas and of course fired a few rounds into them as well.
Then they would kick the front door down and activate Omni tool shields in order to protect them from enemies who somehow managed to stick their gun through a shield.