I know this is supposed to be an expert-level campaign, but I still wanted to beat it anyways, so I had to edit it a lot. I edited it so much that I'm making this repository so that I can publish my changes as a separate campaign on the add-on server. My edits were only targeted at making the main objectives easier; I've also tried rebalancing so that the optional objectives (i.e. killing the enemy leader in a scenario where you're just supposed to survive) are harder. Here's a description of my changes so far:

01 End of Peace: Just some basic gold tweaks. Probably too easy now, but it's the first scenario, so it ought to be easy IMO. Also Vrag is loyal now. 02 The Human Army: Just gold tweaks; add some easter eggs for people using debug mode to attack Lanbec'h 03 Toward Mountains of Haag: Started off as just basic gold/turns tweaks, on another playthru I decided to add some looting events for capturing dwarven villages, too. The dwarven recruiting instructions here are a WIP. In later versions: add "Over the Northern Mountains" to music playlist (since you are going over the northern mountains), use Dwarvish Woodcutters, add dwarf responses to getting looted, have trolls be slowed when they appear (so they don't get to the dwarves before you do), use LIMIT_CONTEMPORANEOUS_RECRUITS, try to have troll AI protect Grüü better, etc. 04 The Siege of Barag Gor: OK now here's where things really start to change. The defenders of Barag Gor kept dying before I could save them, so I had to make them stronger. The shamans wouldn't hit anything whenever they attacked, so I made their attacks magic, partly to increase their hit chances, and partly also because that just made more sense to me anyways? Also I put more villages inside of Barag Gor for healing, and also because as a city, it just made sense to have them. I also made Rugh's death cause defeat, which may seem like it makes it harder, but actually it makes it easier by saving you the time of just waiting around after he dies for the rest of you to die as well, because that's basically what happens when he dies anyways. To make up for his death now causing defeat, I upgraded him into a Nightblade on Easy. I also added some traits to the shamans. While putting "Aged" on the Old one might make things harder, it just made more sense flavor-wise. And the traits I put on the other two were positive. I also gave the defenders of Barag Gor 2 more archers on Easy. Also the usual gold, income, & turn limit tweaks. In later versions: give Rugh and Jetto traits, AI tweaks 05 To the Harbor of Tirigaz: apologize for Holy Water being a red herring, also gold tweaks. 06 Black Flag: Here the enemies kept overtaking me before I really had a chance to set up, so I removed their starting villages so they'd waste more time capturing them instead. I also wanted to give your ally some villages as well, so I made Affman a leader so that his side could have villages. Finally, I also turned the generals into lieutenants in this scenario as well. 07 The Desert of Death: It took too long waiting for everyone to get a chance to recover from their scorpion poisonings, so I added more villages to the map. 08 Silent Forest: basic gold/turns tweaks; use LIMIT_CONTEMPORANEOUS_RECRUITS more; get gold on interrogation; add another village... 09 Shan Taum the Smug: just gold tweaks (at first); I also tried to make Shan Taum's side persistent, but then later decided against it. Gave Shan Taum some guards if he is attacked (since I'm only trying to make the main objectives easier here, not the bonus objectives), and an income. In later versions: add another keep, more gold/income tweaks, modify Shan Taum AI and recruits, give Shan Taum more gold if you try to play too aggressively 10 Saving Inarix: I made it much easier to save Inarix here. I turned Thelarion from an Elvish Champion into an Elvish Hero here, and since he keeps coming back in later missions, I made (or at least tried to make) his side persistent (as well as Darstang's). I upgraded Plonk from a Slayer to a Nightblade to help you break thru the bottleneck on the bridge more easily. I gave Inarix more guards escorting him on easy, and adjusted their coordinates. I also gave Darstang and Thelarion events for when they're attacked. On another playthru, I made the guards on the bridge weaker, and gave the player a hint as to how to break thru them. I also had Inarix reprimand the player if the player forgets to move any saurians on the turn they appear, as I did that once. In later versions: make use of Dwarvish Woodcutters, give Plonk an extra trait (on EASY), give Inarix traits, add some delays to the explosion animation 11 Clash of Armies: I reduced the number of gryphons the dwarves recruit here so you don't have to split your attention as much and can focus more easily. I also reduced the HP boosts for the transport ships so they can be destroyed more easily. On another playthru, I handled the case of the player having an empty recall list when the roles at the start are assigned. In later versions: debug message tweaks, have falcons appear with merfolk on EASY 12 Giving Some Back: basic gold/turns tweaks; also gave orcs starting villages. In later versions: give Arthain more recruits, try to prevent your allies from killing the enemy leaders for you and stealing your experience, have enemies target your allies more 13 The Dwarvish Stand: Started off as just gold tweaks, also decided to give the player a yeti here as it's the first of a series of winter levels. On another playthru, I also let the player start recruiting Frost Stoats and Icemonaxes here, for the duration of the winter, as they are specialized for snowy terrain. In later versions: increase turn limit, use "Over the Northern Mountains", have dwarves use Dwarvish Woodcutters, have bandits use Ruffians and Woodsmen, make terrain snowier (and add snowshoes to compensate), give enemies a bit more gold if you have too much, add events for attacking enemy leaders so that they're better defended, more gold/income tweaks, give enemies more guards, update cutscenes, add sound effects to certain new events so you can tell if they happen or not, even more enemy defenses, etc. 14 Back Home: I used the LIMIT_CONTEMPORANEOUS_RECRUITS and ON_DIFFICULTY macros here a lot. This is about where I started to realize that making Thelarion's side persistent didn't actually work. I might go back and try the persistent=yes method later (instead of the save_id= method currently in use), but knyghtmare says that that method results in multiple Lanbec'hs back in S11 (Clash of Armies)... In later versions: increase turn limit, add more snowshoes, make terrain snowier here too, modify enemy AI, let elves recruit Elvish Horsemen, give enemies more gold if you have too much, etc. 15 Civil War: started off as mostly just some basic turns/gold tweaks. I have also tried to add back the commented-out assassination code. To try to make said code actually work, I felt that I'd need a way to give the player a way to sneak around the front lines to actually pull off assassinations while the enemy still has other units alive, which is why I gave the player (the option of) some additional units, assuming they have either Plonk or Jetto still around. It's still kind of hard to make sure the enemies still have enough units left for one to take over as a leader though; any suggestions as to how to improve this while still keeping it are welcome. In later versions: use "Over the Northern Mountains", increase turn limit, one more pair of snowshoes, make terrain snowier here too, modify enemy AI, disable poison-spreading behavior 16 The Coward: I edited the map here to give the player more keep tiles for recruiting, so they can catch up to the stream on enemies flooding them on time. Also some gold levels tweaks. After the enemy's initial assault wears off they're not left with much, so I added an event when Orga is attacked to give him some gold back to make up for what I took away. Also, now that I allowed recruiting Frost Stoats and Icemonaxes earlier in this campaign, I took them away again after this scenario, due to winter ending. 17 The Human Attack: started off as just gold tweaks; also added an event giving Lanbec'h guards when he's attacked to keep the focus on just surviving, rather than trying to kill him. The guards do drop gold when killed, though, to make sure they aren't TOO overpowering. In later versions: give Lanbec'h more recruits, add a few more events 18 Northern Alliance: again, mostly just gold tweaks. I also tried to make Shan Taum more defensive so he'd defend more against Howgarth rather than killing your green side of orcish allies, but that didn't really work. I mean, it worked in the sense that I saved my allies after I made my edits, but Howgarth still got to Shan Taum before me though. Note that it's possible to use the AI_CONTROLLER thing to stop Howgarth from getting to Shan Taum before you, but as that is going to be deprecated soon, I want to make sure it works even without it. In later versions: give Lanbec'h, Shan Taum, and Howgarth more recruits, modify enemy AI, add an event for Shan Taum being attacked

Note: this add-on was originally part of my generalized mods collection; its history there can be found at: https://github.com/cooljeanius/wesnoth_mods Forum thread here: https://forums.wesnoth.org/viewtopic.php?f=8&t=53597