Campaign battle vs Grey Knights

I played my first battle in the first round of our narrative escalation campaign. It was a quick battle after some of the other players had finished their battle but others were still playing. My opponent's list consisted off a Grand Master with Nemesis Force Sword and Blind Grenades, an Ordo Malleus Inquisitor with Terminator Armour, Psycannon en 3 Servo skulls, 10 Strike Squad marines with 2 Psycannons, Psybolt ammunition and Justicar with nemesis force halberd, a Terminator Squad with Psycannon & Nemesis Force Halberd, 2 Nemesis Force Halberds, 1 Daemon Hammer and Justicar with nemesis force halberd and a Nemesis Dreadknight with Greatsword, Heavy Incinerator and Personal Teleporter. We rolled for mission and deployment and got Purge the Alien and Vanguard Strike. My opponent had 5 kill points in his list, I had six.

My opponent won the roll to go first and deployed first. I deployed the landraider behind some cover and the hellbrute behind it. The two missile launcher chosen squads went into reserve (kill point denial). I then seized the initiative.

In my first turn I moved the landraider forward 6" and shot at the dreadknight. I scored one or two wounds. The helbrute moved with the landraider, keeping behind it for cover.
In his first turn he moved his units a bit around. Most of his psycannons were out of reach of the landraider but he still managed to stun it, taking off it's first hull point. The dreadknight moved forward and tried to find some cover.

In my second turn both my squads of chosen arrived. Not what I had intended. They shot snapshots at the strike marines and killed at least one. The landraider also snapfired but didn't do much. I thought extra armour wasn't a good option any more but for a landraider it may still be worth its points.
In my opponent's second turn he jumped forward with the dreadnight towards the first squad of footslogging chosen. He shot them but I made my saves and then he assaulted them. I challenged with my champion, sacrificing him to save the other marines in the squad. The psycannons on his other squads stunned the landraider once more, taking off it's second hull point.

In my third turn I disembarked Abbadon and moved and ran him towards the dreadnight with the helbrute right behind him but they were still a long way ahead. I assaulted the dreadnight with the second chosen squad and sacrificed that champion as well in another challenge. Unfortunately one of the squads broke from combat and ran off the table, giving him first blood in addition to the kill point.
In his third turn he destroyed the landraider with his psycannons. The third chosen squad got out and got pinned. He also destroyed the second missile launcher squad in close combat and consolidated away from Abbadon.

In my fourth turn, Abbadon and the hellbrute moved closer. The hellbrute shot it's multimelta at the dreadnight but missed. Abbadon was too far away for the charge.
In my opponent's fourth turn, he used the dreadknight's teleporter to get next to my landraider, leaving Abbadon and the hellbrute away from any targets. With most of my stuff out of line of sight thanks to the terrain, he had no targets to shoot at.

In my fifth turn Abbadon and the helbrute came out in the open and ran towards his troops. The remaining chosen moved into the landraider's crater and shot their melta's at the dreadknight, killing it.
In my opponent's fifth turn he shot at Abbadon (who took a wound) and the helbrute (who made his cover save behind Abbadon). He also moved his forces back from my approaching models.

We got a turn six. In my sixth turn Abbadon and the helbrute moved closer. Abbadon made a charge towards the strike marines. He made the roll even though it was far and through terrain. He challenged (as he has) and killed the justicar.
In his turn, my opponent kept moving back with the terminators and his HQs. In combat, Abbadon destroyed several strike marines and they failed their morale check and ran away. Abbadon consolidated one or two inches. He also stunned the helbrute.

In my turn seven Abbadon moved through terrain and tried to assault the terminators but failed to make the assault.
In my opponent's turn, the strike marines regrouped. He then shot Abbadon down with the terminators. In the campaign we have to roll on a table to see if a special character suffers an aftereffect from being "killed" during a battle but he made it through without permanent injury and can fight again next battle.

In hindsight, I shouldn't have tried to go after the dreadknight. I should just have moved flat out towards his terminators. The landraider would normally have survived a round of shooting. I would then have been able to assault the terminators and his HQs with Abbadon and challenged my way through several kill points.