Instead of following the movement rules for Super-Heavy Vehicles, Super-Heavy Walkers move 12", exactly as if they were Gargantuan Creatures, except that their maximum movement may be reduced by Drive Damaged results, as normal for Super-Heavy Vehicle.
In the Assault phase, Super-Heavy Walkers once again follow the same rules as Gargantuan Creatures (including ignoring armour saves, extra armour penetration, dealing ordnance-level damage, stomp special attacks, the Terrifying special rule, etc)
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