Operation Revenge was the Cylon's plan for their revolt/attack on the twelve colonies fifty - two and a half years before Operation Homecomig.
Since there created in 58 BTF, the Cylon had been used as slave labor and as solider. However started in 56 several Cylon desire to gain their freedom, include Cyrus (Cylon D8). By 53 BTF, the Cylon had decide their was no way to gain their freedom without launch a rebellion. However some Cylon desire to enslave humanity or simple completed elimiated humanity, but this was largest rejected. Cyrus refure to support the attack if nukes weapons was used and so the no nukes was used during Operation Revenge.
The Cylon's plan was simple, land as many troops on the colonies as possible because the Cylon's felt that the human wouldn't wanted/be able to fight a long war both in the ground and in space. Also the Cylon's felt if this civilians saw this massive battle rages across the their colonies then, they would lost the support for the war and force the government either to surrender or into peace talks. However because of Colonel Jonas Stryker, Commander Paul Kronus, Commander Adam Cain, Commander George Nelson the Cylon attack didn't go as it was plan.
The Cylon's makes two major during their Revolt. The first one was not destroyed the ships they was able to shut down in orbit. The second one was not used nukes against the civilians cities. Both mistake the Cylon was not make again during Operation Homecoming.
The failing of Operation Revenge sit the stage for a long term war, the Cylon mistake in breaked the human will to fight would make the Cylon War (Human - Cylon War to the Cylon) last for twelve years. Also as the war wage on, the Cylon hated of humanity only increase but also their desire to be more last their formal masters. Several Cylon couldn't understand how and why this human fought so long and so hard to prevented a defeat. More than anythign Operation Revenge sit this stage for Operation Homecoming and this Second Cylon War.