YGO OCG News

Since the other card information(s) have been released, I decided to make an analytical review based on these two monsters. Based off the Dark Synchro monsters that the Dark Signers have used in the 5D's anime, these card(s) have been made into actual Synchro monsters in the OCG.

First, their stats/requirements.
Underground Arachne is a Level 6 2400 ATK Synchro Monster (decent attack but still no Goyo Guardian). Similarly, Zeman is a Level 7 2500 ATK Synchro (compared to other Level 7 Synchros, this is so-so). To summon them, you must obviously use a DARK (attribute) Tuner monster (which are plentiful especially given Level). Other monster(s) must be of the same type as the Synchro you are trying to summon. So for Underground Arachne, insect and for Demonic Monkey King Zeman, beast.
Egh, don't know about this requirement since typically DARK Tuner monsters follow some type guideline. Also, Insects and Beasts are not the most commonplace types in this format.

Second, their effects.
Underground Arachne has the effect that was mostly restricted to Ancient Gears. While this is no Ancient Gear Golem (3000 ATK piecer) or Ancient Gear Gadjitron Dragon (3000 ATK with multiple effect[s]), it kinda helps since this thing doesn't have the best ATK. Once per turn, it can treat a face-up monster on your opponent's field as an equip card, preventing its destruction. I don't know if this means you can only activate this effect if you do not have a monster equipped to it OR if it is a once-per turn effect. Judging by things, it seems to be the former. Rest of the card text is unknown, but I assume it keeps the anime effect of destroying the equip card in its place when destroyed.
Demonic Monkey King Zaeman also has the same Ancient Gear-like effect that Underground Arachne has, but with 2500 ATK and a moderate amount of Beast cards, can take advantage of this more than UA. Its second effect is that by discarding a monster from your Hand, you can negate an attack. Good for your weaker monsters, I suppose.

Coupled with One-Hundred Eye Dragon, these "Dark Synchro" cards seem to be nothing in the actual OCG. I don't expect them to be used in any real deck, especially given their summoning requirement which really does not fit with anything.