Don't play DW 6, I advise you, you would be thoroughly dissapointed.
True the gameplay and the mission has increased a lot of difficulty with more on time strategy and less lag from how everytime you:
defeat enemy officer = Meet officer quote "stand and fight!", Defeat "I lose", "There goes another one", Praise "Earned my praise warrior"
into
"No one can defeat me!" (Morale Up!) (Occasional Praise when you are near to a base etc)
Enemies are also harder to kill with no Charge Attacks but replaced with Unblock Attacks.
Your former charge attacks are now replaced with a specific chain attack that kills blocking targets by bumping them upwards, you then rely on how well you can link your attacks while keeping enemy rooted unblocked. (On Chaos difficulty, this is near impossible as enemy AI is strong, and tricky because new blocking system incorporates back blocking as well, so you cannot advance to the back and attack, it won't work.)
Formerly, some charge attacks are increased with efficiency when you can basically plow through enemies without unblocking them with "Flash" as a skill, or "Boost" to cost significant damage when not blocking.
In DW6, the element is gone making killing enemies like Lu Bu (very strong mind you, even in easy mode) impossible.
Quick jumpers like Lu Xun and Gan Ning make some of the most difficult enemies ever.
That said, there are plenty of redeemable characteristics from the game.
I like the new ambush system where if you pop by a blind corner of a descending hill and so on they will be feared and your enemy can panic. (Unable to guard and significant HP loss)
They took the PSP Base takeover system for this new game, so you kill off soldier bosses (captains etc) to obtain bases for morale, but your enemies can do the same so the challenge is remarkable.
Soldier AI has also increased, making hard mode even very difficult.
I like the Skill Points thing, but annoying as they are mostly the same. There is only 4 different Special Skills.
: Swift Attack - Increases attack rate and agility rate exponentially, pair this with red blood true musou = near 2 hit or 5 hit kill. (even in Chaos mode)
: Rockfall - Summon rocks to fall from the sky, high damage low accuracy.
: Fire Attack - Summon bolts of fire from the sky or from the ground, sets bases on fires to lower morale quickly of enemies, best ability, and takes over bases in a breeze.
: Running Attack - run and hack slash enemies (useless unless you are very good at controlling where you character runs, consider the number of obstacles even in a base, it is hard to actually cut anyone at all.)
I don't like the new weapons selection however, you get weapons on 3 different elements, not ranks. Elements are Skill, Standard, Strength. The attack level increases, and that is all you will get regardless how well you played in Chaos mode or etc.
Skill weapons seemed to have more attributes to them, (max 4) and concentrate on how well you can use said weapon to strike enemies more, such as concentration, airwave, etc.
Strength weapons like namesake, normally comes with True Musou (which is stupid consider it meant slow animation and extra fire element, best paired only if you have red life bar)
Standard weapons increases reach significantly, so Gan Ning in this case, can reach enemies far beyond his normal length.
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I'm not sure if Survival Mode changed or not, but originally back in 2, it was certain missions on certain floors (starting at... I believe 60F at the earliest and going up to 99F) that could net you a rare skill at level 4 if you had already obtained that skill at level 3.
Either way though, once you get Awakening 3 on any character you're set on most difficulties anyway due to the sheer destructiveness of Death Element. A couple characters might want custom level 3 weapons to add to DEF though, like Masamune, simply because of their low natural abilities in it, if you plan to attempt Chaos/Expert Dream stages...
Not gonna argue with Gracia on that... somewhat awesome because of her horseback riding though my main horseback character now is Nobunaga.
Survival mode has not changed in XL, you can get the same things etc. So yeah Greed 4 etc.
I personally don't like the Death element, because at some point, using characters like Musashi to clear survival modes make it impossibly difficult to kill people. (It is damage caused by percentage of HP, so as HP draws lower, the percentage downs to minute proportions like 0.000001 % damage per hit, useless.)
At Awakening 4 however, that changes significantly with all elements.
Also...
Lightning, the rest of the elements are generally useless compared with lightning.