Cards with peculiar conditions can introduce strange new "rules" for duelists to follow. These rules-of-thumb stick with players long after their connected card is lost to time.
Hand Traps
Since the release of Gorz the Emissary of Darkness, hand traps have changed the way we think. Hand traps normally have a condition that can be played around.
Gorz the Emissary of Darkness
Rule: Attack from lowest Attack to highest attack.
Speaking of which, Gorz the Emissary of Darkness hasn't been used for a while, but still terrorizes veteran duelists. The proper way to play around Gorz is to attack first with your weakest monster, then in order until your strongest. Gorz is not as great anymore, since summoning a strong token isn't a big deal in the modern meta. But the impact of Gorz from his own time that has ingrained this line of attack can still be seen.
Effect Veiler
Rule: When possible, activate effects during the Standby or Battle Phase.
Waning in and out of popularity, Effect Veiler is the previous side grade of Infinite Impermanence. That being said, it has a weakness in that you can use it only during the opponent's Main Phase. Thus, if an effect can be activated during the Standby or Battle Phase, that would be for the best. An example is using Sky Striker Ace - Raye during the Battle Phase, to prevent Sky Striker Ace - Kagari from being negated by it.
Nibiru, the Primal Being
Rule: Summon a negation before the fifth summon, summon less than five times, or be prepared for the worst!
Of course, Nibiru, the Primal Being's impact has been massive. It reminds me of the Maxx "C" challenge from days yonder. Combo players can attempt to ignore it, at the risk of being completely blown out. However, Nibiru's influence has resulted in a focus on combos that can put out a monster negate before or on its fifth summon.
Board Position
Links are an obvious change to how we position our boards. Even before then, we have had to worry about our card's position relative to our opponent's.
Mekk-Knights
Rule: Don't place cards parallel to each other.
Mekk-Knights can special summon themselves if there are two cards on the field parallel to each other. Link monsters have to be summoned into the Extra Monster Zone, so it may be wise to avoid setting traps parallel to those positions.
Infinite Impermanence
Rule: Activate Spell cards in non-parallel zones to face-down Spell or Trap cards.
Likewise, a spell or trap parallel to Infinite Impermanence's position when activated is negated. I am sure many games have been lost because of this. Generally, Spells should be activated non-parallel to the opponent's set spell/trap cards.
Link Arrows
Rule: Avoid the Extra Deck Monster Zones when summoning.
Obviously, any additional Link monsters must be summoned into zones linked to the EDMZ. But our own arrows are not the only consideration when summoning.
The most dangerous spot to keep a monster is parallel to an Extra Monster Zone. Relinquished Anima, Crusadia Equimax, and Topologic Trisbaena all take advantage of that spot. In the case of Trisbaena, you just need to avoid summoning into it. But for the others, they can appear after the fact and take advantage of the poor positioning.
Battle Position
Rule: Defense Position is safer than Attack Position.
It would seem normal to summon your monsters in the position in which their stats are highest. But with the advent of certain cards, there are other considerations.
Number 101: Silent Honor ARK
Number 101: Silent Honor ARK can remove monsters without destroying or sending them to the Graveyard. This was most useful against cards like Mecha Phantom Beast Dracossack or Evilswarm Ophion in its own time.
Lightning Storm
A modern example, but with the same counter play. While the focus has shifted from hard to destroy beaters to negation on legs, the concept is still the same. You want to put your monsters with negation effects in Defense position to avoid this common staple.
Tributing Removal
Monsters that tribute your opponent's monsters are the hardest forms of removal. They leave little room for response, meaning any counter play has to be performed before they come out.
Kaijus
Rule: Consider splitting monsters that can be split during the Standby Phase.
While there is little to do against Kaijus, some monsters that have "split" effects like Ritual Beast Ulti-Cannahawk and ABC-Dragon Buster can prematurely escape. This does limit their flexibility, or in ABC-Dragon Buster's case, limit your disruption ability. But the mere existence of Kaijus cause this kind of thinking.
The Winged Dragon of Ra - Sphere Mode
Rule: Consider leaving less than three monsters on the field.
They say in formats where wide negation boards are present, it will descend once again. Jokes aside, The Winged Dragon of Ra - Sphere Mode is a rather specific case. It cannot tribute your opponent's monsters unless they have at least three… meaning that in game two and three, players may consider keeping their board smaller.
Extra Deck Influence
The very existence of some cards can even impact the Extra Deck. These examples are very specific, yet the adaption to these cards show the savvy of the player base.
Chimeratech Fortress Dragon
Rule: Don't leave Cyber Dragon on the field.
A bit of an oldie, but Chimeratech Fortress Dragon presents one fundamental for Machine decks; do not leave Cyber Dragon on the field! For now, Cyber Dragon players can rest easy. But be weary if a Machine deck ever comes back into the meta.
Dogmatika Maximus
Rule: When using Maximus, prepare to lose a few cards, or for the opponent to summon Invoked Mechaba.
In the opposite manner, Dogmatika Maximus changes the Extra Deck. Decks that can't even use Elder Entity N'tss, Cyber Dragon Nova, and Invoked Mechaba tech them in to fight off Maximus.
Conclusion
Half history lesson, half practical application, knowing previous and current rules-of-thumb is both an interesting and useful affair. Knowing the nuances of dueling and practicing them may just give you the slight edge to consistent victories.
