In recent days, the portal had continued to expand. Once it had grown large enough to allow the Emperor Doomblade through, its rate of expansion slowed once more. Father Ohm, who had been studying the portal all along, claimed that its expansion had reached a threshold. If they wanted it to grow further, they would need to send troops through and use their presence to strengthen the connection between the worlds on either side of the gate.
Colonel Leithris dearly wanted to lead the remaining armored forces through and avenge their comrades, but he remembered Leman Russ's orders before he left with perfect clarity.
Wait for reinforcements. Gather strength.
Under Primarch Leman Russ's orders, many armies engaged in purging xenos converged on the portal. Before long, it was no longer guarded solely by the battered Yad 227th Infantry Regiment and Hammer of Destruction Heavy Armored Company.
Father Ohm had even received a transmission from the Adeptus Mechanicus. Two Knight houses with glorious traditions were advancing alongside a research fleet. Before long, his work would receive the aid of more colleagues.
Father Ohm gladly accepted the material support, but he was dissatisfied with other tech-priests trying to meddle in his work. If he could unravel the secrets of the portal alone, his name would be cast in alloy on Mars for future generations to praise.
Mustering, preparation, communication.
In just three days, the positions around the portal had temporarily gathered five hundred thousand soldiers, three hundred and sixty Leman Russ tanks, one thousand four hundred Chimera armored vehicles, eight hundred and fifty Sentinels, and two thousand four hundred artillery pieces. Three frigates fitted with cargo holds supplied this force. They remained in orbit above the barren planet, relying on transport craft operating day and night to deliver supplies to the ground.