Firstly I would like to apologise to all nurgle fans that unfortunately due to not knowing the chaos codex that well anymore I wasn't aware that typhus's daemon weapon wounded on a 4+, as such with this weapon and its D6 extra attacks, there is an extremely good chance he could beat the Deceiver. As such I am re-running this fight now. (thanks crispy for the heads up) this actually ended up a pretty good battle.
The C'tan are monsters of the highest order, gods in semi physical form and very hard to kill, this god, the Deceiver is the lesser of the 2 and correct me if im wrong but doesn't really seem to have anything that would take effect in this battle, i dont allow running away from combat, pinning etc as such it has only combat and is purely an eternal warrior monstrous creature with an extremely good stat line and 4+ inv save.
The Deceiver vs Typhus
Deceiver begins by charging into combat, due to defensive grenades he gets 4 attacks on the charge. He hits scores 2 hits and 1 wound, putting typhus on 3 wounds after his save is failed. Typhus hits back with 5 hits (due to a 6 on the daemon weapon) and then gets 3 wounds, 2 are saved, taking the deceiver down to 4 wounds.
Next round and the deceiver scores 0 hits with 3 1's and a 2. In reply Typhus hits twice and wounds once, then with a 4 rolls 1 more hit from his daemon. Both hits fail to wound.
Deceiver this time gets 1 hit, it wounds but its saved. Typhus scores 5 hits with the help of 3 attacks from his weapon, those hits turn into 3 wounds and 1 is failed leaving the deciever also now on 3 wounds.
Next round and the deceiver scores 3 hits, 3 wound and unfortunately all are failed killing Typhus however since they are at the same time typhus has a chance to bring it back (double deaths come back both on 1 wound) he rolls a 4 on the daemon weapon and then gets 5 attacks, followed by 3 wounds, 2 saves are made and the deceiver ends the round as winner.
Typhus casts wind of chaos, it wounds but is saved. Onto combat and he rolls a daemon 3, which leads to 4 hits, 4 wounds and 2 failed saves, leaving the necron lord on 3 wounds. He hits back with 1 hit and 1 wound and the save is failed, leaving Typhus also on 3 wounds.
Next round Typhus rolls a daemon weapon score of 4 leading to a total of 6 hits, these turn into 4 wounds, averages work out and 2 are failed, putting the Deceiver on 1 wound. In reply he hits twice but does not wound, scoring a snake eyes.
Into the next round and typhus scores a 6 for his weapon, this results in only 3 hits however turning into 1wound however it's enough and the Deceiver dies. His attacks back get 1 hit and 1 wound, putting typhus on 2 but it's not enough and typhus takes the round.
Essentially a mirror of last round this time as the Deceiver gets no charge bonus and has no shooting, we begin with wind of chaos, but it does not wound. They go into combat, Deceiver scoring 3 hits and taking 2 wounds from Typhus. In reply daemon gets 3 attacks, leading to 3 total hits, this ends up with 2 wounds and both failed on the save, results are tied and Typhus is on 2 wounds, Deceiver on 3.
Next round and Deceiver gets 2 hits and 2 wounds, both are failed and Typhus dies, before that however he gets 2 daemon attacks, resulting in a total of 2 hits, 1 wounds but its saved, The Deceiver wins, his inv save and needing 4's to wound yet his only wounds only needing 2's in the end just edges him though.
This was worth running again, Typhus could have done it but in the end the initial result stands.