There is much material that has been written on how the Imperial Guard in general was seldom in combat. In actuality, that does apply to the Old Guard infantry regiments, the Grenadiers a Pied and the Chasseurs a Pied.
They did fight at Marengo in June 1800, saw some action at Eylau in 1807, stood firm under the intense bombardment by the Austrian 200-gun battery at Essling in 1809 and some of them reinforced Lauriston's 102-gun battery at Wagram when the artillery losses in that battery began to grow. They were engaged periodically during the great retreat from Moscow in 1812, definitely were engaged at Hanau in 1813 and fought during the campaign of 1814 in France. In 1815 they were engaged at Ligny and five Old Guard battalions made the final French attack at Waterloo and lost outnumbered against the allied center. Two battalions successfully counterattacked at Plancenoit on the French right flank after the Young Guard division was ejected from the village by the Prussians. The 1st Grenadiers a Pied stood firm among the rout at the end of the battle and withdrew in perfect order.
There were usually only one regiment each of grenadiers and chasseurs a pied in the Guard, sometimes increased to two each, but the latter was for only a brief period. In 1815 there were four regiments of each.
For the rest of the Guard, the situation was different. The cavalry of the Guard was usually engaged and charged at Austerlitz, Eylau, Wagram, in Spain, and was actively in the fighting in 1814 and at Waterloo.
The infantry of the Young and Middle Guard fought hard beginning in 1809 at Essling and was usually employed in combat in 1813, 1814, and 1815.
The artillery of the Guard after being expanded with the organization of the regiment of artillery a pied became the artillery reserve of the Grande Armee and fought hard at Wagram, Lutzen, in 1814 and 1815.
What is usually overlooked, though, is that the Old Guard infantry regiments were veterans and had done more than their share of fighting surviving various fields to become eligible for entrance in the Imperial Guard.