When the Clanners finally decided to take active interest in the Inner Sphere , they had functionally no working knowledge on the present state of the Inner Sphere. So they settled on sending a group of mostly freeborn (naturally born) mech pilots into the Inner Sphere under the guise of a new mercenary company by the name of the Wolf's Dragoons. Their original goal was to scout out the state of their promise land. 

The Clanners firmly believed that the Inner Sphere would be behind them in technology as they had been taught since the time of Nicholas Kerensky. As such the spies were sent with some of the oldest mechs the Clanners had, but to further the ruse, these mechs were downgraded. The Clanners were right, but they had no clue how right they were. The 4 Succession Wars had nuked the industrial base and the intellectual base to hell and back of the Inner Sphere. They brought shitty Clanner mechs that still outclassed almost anything the Inner Sphere had. Among these was the Annihilator, a mech that was built after the Clanners' predecessor, the Star League in Exhile left the Inner Sphere. Meaning this mech literally did not exist in the Inner Sphere before this and it drew immense interest and curiousity from the Great Houses

The Wolf's Dragoons coming into the Inner Sphere with their downgraded "oldest mechs"