Based on the latest market prices tracked on TCG Stacked, a foil copy of Mortarion, Daemon Primarch is worth about $6.56 USD
X but now once I've actually looked at the card I realized it is a pretty decent card, just because it doesn't have any physical attacks doesn't mean the card isn't any good
Using cards like Entomb or even Final Parting makes assembling Eldrazi-Angel-Exodia pretty easy in Commander, and there arent that many ways to stop it, especially given it stops a Cyclonic Rift (because the spells mana value is still two, even when overloaded)
Finally, "Junk Converter" can discard itself to search "Junk Synchron" and thus Special Summoned with the latter, and then can Special Summon a Tuner monster to continue Synchro Summoning
If the returned creature has double strike, it will deal combat damage only once during that regular combat damage step