From the release:
Similar in aspect to the Contemptor Dreadnoughts of the Legiones Astartes, the Contemptor-Galatus is a markedly superior war machine. The unrivalled skills of the warrior entombed within its sarcophagus notwithstanding, the Contemptor-Galatus is stronger, faster and better armoured.
Designed as a high manoeuvrability hunter-killer, the Pallas Grav-attack is a rapid strike vehicle utilising advanced repulsor-lift technology. Filling a similar battlefield role to the various patterns of Land Speeder and Attack Speeder of the Legiones Astartes, the Pallas has superior agility, improved armour, inbuilt shielding technology, and more powerful weaponry in the form of its twin-linked Arachnus blaze cannon – an expertly engineered weapon that can successfully eliminate both infantry and armoured targets.