It's very easy to miss even the most basic functions or utilities in video games now a days. Even as someone who has been playing MMORPGs for over a decade, I often miss the most elementary features in a game that make life SO much easier.
I've noticed that a lot of video games offer "tips" during loading screens. And while at first thought they may seem incredibly basic and elementary, sometimes I read a tip and I'm like WHOA WHAT REALLY? I CAN DO THAT?
I think it would also be very helpful for new players.
The list could go on and on but I do think that some of these features remain hidden to new players and sometimes even veteran players for quite a long time.
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EDIT: Since apparently this feature might be in development, let's compile a list of helpful tips for adventurers of Eorzea. Perhaps they'll include them in the list!
COMBAT
-The spell Virus reduces the target's DEX and STR by 15%. If used with Enhanced Virus, it will also decrease the target's MND and INT by 15%. (Credit: melflomil)
-It can be difficult to spot an enemy's back or flank if it doesn't look like a human or animal! Look at the ground arrow on its target indicator to see which way the enemy is currently facing.
-FFXIV features two different movement systems using a keyboard. You can toggle between legacy and standard in the character preferences. Try both and decide which best suits your playstyle.
QUALITY OF LIFE
-You can set up to 3 favourite Aetheryte destinations. These destinations can be traveled to at a reduced fee.
-You can type <pos> in chat to show your party members where you are.
-Clicking on a posted position in chat brings up the map for that zone, as well as marking where that location is.
-You can type <flag> in chat to link the currently flag on your map in chat, even if you are not at that location!
-You can click on an Aetheryte on a map to travel to that location.