Boil him, mash him, put him in a stew?
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Definitely the trickiest thing is getting him into combat, as otherwise he's a really solid all rounder character.
Honour Guard being Elites definitely opens up new options as they have the same getting-into-combat problems as he does and have access to AP2, but unfortunately can't be taken as part of the basic demi-company structure.
Here's the thing though, you don't
need him to be able to play Salamanders (yay!) as the basic tactical squad can already take a Master-Crafted Combi-Melta. I think that when combined with a Plasmagun it plays better most of the time at least, than when combined with a Meltagun.
You also already have access to double (effectively Twin-Linked) Flamer Assault and Bike Squads, and (effectively Twin-Linked) Heavy Flamers with Dreadnoughts and Sternguard.
Vulkan's key ability is putting Master-Crafted Combi-Meltas on Sternguard (though is very expensive!) and more importantly Master-Crafted Multi-Meltas in Tactical Squads (yes they're really are worth it when MC'd), Attack Bike & Land Speeder Squadrons (but speed isn't Salamander's thing, fluff-wise), and on Dreadnoughts too (Deep Strike ftw!)...
If you're not fielding these squads then take a Captain / Chapter Master with the Burning Blade and a Bike / Jump Pack / Terminator Armour.
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In short a Honour Guard and Multi-Melta heavy army is probably the best
Perhaps for a 1500ish list:
Vulkan He'stan
- Gauntlet of the Forge, Kesare's Mantle, Spear of Vulkan
- Iron Resolve
Honour Guard Squad (
- 270
- Chapter Champion, Master Crafted Relic Blade / Thunder Hammer
- Chapter Banner, Power Sword
- 4 Power Axes
- 2 Power Mauls
Land Raider Crusader - (250)
- Master Crafted Multi-Melta
Dreadnought - 145
- Master Crafted Multi-Melta, Powerfist with Twin-Linked Heavy Flamer
- Drop Pod
Tactical Squad (10) - 210
- Master Crafted Combi-Melta
- Plasmagun
- Master Crafted Multi-Melta
- Drop Pod / Rhino
Tactical Squad (10) - 210
- Master Crafted Combi-Melta
- Plasmagun
- Master Crafted Multi-Melta
- Drop Pod / Rhino
Attack Bike Squad (2) - 100
- 2 Master Crafted Multi-Meltas
Assault Squad (5) - 120
- Veteran Sergeant, Master Crafted Power Maul, Bolt Pistol
- 2 Twin-Linked Flamers