A lot of stuff was done for the 5th edition codex (2011), but a fair amount of that was characters and vehicles.
That essentially leaves 2 dual kits (4 units) of infantry (most of which fall under elites)
Triarch Praetorians & Lychguard.
Both of these have downsides
Lychguard downside is that they're slow moving close combat units. 9th is.. unlikely to fix this (especially as there are a bunch of new close combat units to sell)
Triarch Praetorians are jump infantry, so a lot faster, but are explicitly not part of any dynasty, which causes problems (they get no subfaction benefit). On paper they should be good (fearless, durable, good strength, good
AP), but they don't really impress people, and the many points adjustments seem to show that
GW can't properly evaluate them.
Second Dual kit is the Deathmarks and Immortals
Deathmarks are elite, short range snipers... with fairly crappy guns and a clunky ambush rule. They cause additional mortal wounds on 6s, so if you like crit-fishing, they aren't the worst thing, but otherwise they're basically marines -1 (at primaris point costs, at least originally).
[Immortals] are troops and currently the go-to unit for Necrons. They can take tesla carbines or gauss blasters, and current math makes tesla better. Assault 2 and every 6 is 3 hits instead of 1. Blasters are rapid fire 1 and
AP-2.
Mathematically, tesla currently wins. That
might change, but it would be a pretty major and unexpected overhaul.
This is pretty much the winner when it comes to Necron infantry.
Competitively, Warriors and Flayed Ones don't even rate. We don't know if flayed ones are getting updated (they aren't in any of the photographs, but without a major rules overhaul, it doesn't matter)
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TL,DR Immortals. Immortals with tesla carbines.
Pretty much the only infantry option that fits your criteria. Optionally blaster immortals as a small backup unit to hedge bets.
Some of the others might get fixed, but no guarantees
AnomanderRake wrote:Resin characters, Warriors/Scarabs, Destroyers, and the Monolith probably are going to get updates since they're either resin or pretty old, but the rest of the range is pretty safe.
We know for a fact that warriors and Monoliths absolutely are getting updates. There is no probably here.
New scarabs appear in one photo, and a new destroyer does as well, but it isn't clear if that's the new 'normal' destroy or a character version.
Most resin special characters will likely stay (with the obvious exception of Szeras, who's coming alongside
Pariah). The resin lord is likely to be replaced by one of the new models pictured, and the resin overlord is already redundant twice over (overlord plastic kit and overlord from
CCB/Annihilation Barge)