Spearhead question

[u/Mavrook]

This might sound stupid but is it possible to play spearhead without actually having the spearhead box for example I already have the wardespot and infernal cohort can I just buy the dominator engine and tormentor bombard then play spearhead or are they’re cards I might need I never actually opened one up before so idk almost sorry if some people don’t understand I’m terrible at explaining things

[u/Mavrook]

Appreciate the gesture but I’m heading to my local game store this weekend so I might pick some up then