The XIIIth Legion's Armour deploys in force: Korinthion V Campaign Update

On Korinthion V, the Ultramarines continue their efforts to harass the Iron Warriors and prevent them from rallying from their failed interception of the Spear of Konor.  Hoping to revive their fortunes they deploy a Sicaran to add more heavy support.  However, the Iron Warriors manage to Seize the Initiative and strike first before the XIIIth Legion can begin their advance or fire their first volleys.  Identifying the Sicaran as an immediate threat, their Basilisks and Siege Tyrant Terminators concentrate their fire, crippling the tank. A tactical support squad armed with melta guns strike from the subterranean depths to finish the job.  Losing such a high-value unit is a crippling blow so early in the battle and it is already looking grim for the Ultramarines.

The XIIIth Legion's armour advances aggressively under heavy bombardment

The Ultramarines' new Sicaran was a high priority target for the IVth Legion

However, the fact that the Iron Warriors have focused so much of their devastating firepower on the Ultramarines' Sicaran means that their other units are able to move forward unscathed.  They also deal efficiently with the arrival of two Terrax Pattern Termites from the subterranean depths, their Contemptor Dreadnoughts watching and waiting for such a threat.

The XIIIth Legion box in an Iron Warriors' breacher squad assaulting from underground in their Terrax Pattern Termite

Always a threat: the Iron Warriors' Tyrant Siege Terminators

The XIIIth Legion's only hope, though, is to get their Land Raider sufficiently far across the battlefield so that the Suzerain can assault the IVth Legion's dreadnoughts.  Aware of the threat, the Iron Warriors focus their fire on the Land Raider but it manages to last sufficiently long to allow the Invictarus Suzerain to disembark into cover.  Supporting their advance, a tactical squad with melta guns deploys out of a Rhino Armoured Personnel Carrier, destroying the first of two Contemptor Dreadnoughts confornting the Suzerain Invictarii.  The Ultramarines' Honour Guards soon finish off the second and survive the bombardments aimed at them. The same can not be said for an unfortunate tactical squad caught in the shelling; the Iron Warriors' warsmith displaying a typical disregard for his own troops.

The Ultramarines' Invictarus Suzerain squad brace themselves for the charge of an Iron Warriors' Domitar Ferrum Battle Automaton

The Ultramarines' Suzerain Invictarii manage to survive the brutal charge of a Domitar Ferrum Battle Automaton, hacking it to pieces with their thunder hammers and Legatine Axes.  They prepare to charge the IVth Legion's Deredeo Dreadnought.  But with more rhinos bearing down fast, as well as the Ultramarines' own Contemptor Dreadnoughts the IVth Legion's Warsmith orders a hurried retreat and the Ultramarines have turned adversity into victory.