Most members share the effect "If this card attacks, it is changed to Defense Position at the end of the Battle Phase, and its battle position cannot be changed until the End Phase of your next turn." (though not necessarily with the same wording) and also share 0 DEF.
"Goblins" have an enormous advantage in ATK. Because of this advantage, "Goblins" may be the strongest Level 4 monsters. However, though the "Goblins" have several advantages in their original ATK, they have a drawback that makes a Deck containing them somewhat hard to use. This drawback is that after most "Goblin" monsters battle, they must change into face-upDefense Position. So, this Deck will be tricky to use in tournament play. To prevent this drawback, you can add copies of "Final Attack Orders". They will help you optimize the "Goblin's" strength. You can also use "Skill Drain" to prevent this effect while negating your opponent's card effects at the same time. You can also use "Zero Gravity" when most of your strong "Goblins" are in defense to switch them to attack, or for an added bonus use "Gamushara". ("Zero Gravity" switches all monsters from their previous positions ex. defense to attack or attack to defense). These cards would also work well in a "Spider" Deck and "Clown Control" Deck.