Their unique units are Flamer wielding jet pack marines, a nice anti horde but not the best against marines as they still only have 3+ armour. Also we have 2 wound mega possessed, who are very powerful in combat but they can never score and need an assault transport to be effective. We also get a possessed contemptor dreadnought who works really well against psykers and demons (both of which we use and have so be careful).
Extra close combat weapons/chain swords are all ways excellent and will pay for them selves in one round of CQC. With our better morale legion Vexila aren't that useful. Nucio voxes are good if your deep striking with pods (legion ones are special will cover this later) but as WB aren't going to be investing in barrages weapons (you're not an iron warrior) they often won't be effective for you.
Sergeants should be taking artificer armour to reduce combat loses and power swords to maximise enemy casualties, don't challenge with them as they won't be able to make use of their power swords against* artificer armour sergeants. Melta bombs are always a yes, combi-weapons not so much: individually they aren't effective.
With special characters and diabolists we gain access to a random d3 table granting: hatred and zealot/+1str or finally the demon rule which grants a 5++. Arguably the best is +1 Str, 5++ is nice, and hatred is better than demon. Demon also counts as destroyed at the end of the game and can no longer score. Demon confers fear but with legion morale being 9 normally this is not something to count on but is very nice when it goes off*
Very brief over view of Word Bearers for those deciding on their legion. Will be doing a tactical squad blog later.
That was the moment the sky tore open. Stormclouds formed from the ghosts of a hundred murdered worlds began to rain blood on the dead city below.
Quote from Betrayer by Aaron Dembski-Bowden pg 379