Requires SkyUI, unless you download the No-SkyUI version (which will not include a MCM menu through which you can customize the mod). Info about the No-SkyUI version, including install instructions, are in a separate section below.
DLCs are not required if you download the No-DLC version, but they are required for the default download.

Manual Installation: Extract all files into your /Skyrim/Data/ directory. Enable the .ESP file in SkyrimLauncher -> Data Files.
MO or NMM: Just install and enable it.
Regardless of which installation you choose, you should install the hotfix file as well. Download the zip and extract the files into your Data directory, allowing it to overwrite the old files.

Load order doesn't matter for main file.

As always, keep a backup save from before installing any mod. If you have any issues, uninstall the mod and revert to your old save.

Optional files:
These must be used in addition to a main file.

• Deadly Dragons Patch: Thanks to Mur4s4me and euphoricknave we now have a patch for Deadly Dragons! This will allow the stat boosts, knockdown, and stagger resistance effects from DD to apply to my dragons. You must be using the full version of DDC2 (not the No-DLC or No-SkyUI versions). Place this patch file after both DDC and DD in the load order.
• Force DDC Only (ogDDC2_ForceNoPluginDragons.esp): This removes all non-DDC2 dragons from the leveled lists so that you will only encounter DDC2 dragons. This file must be placed at the bottom of the load order (or at least after all mods that edit dragon leveled lists). That means even after bash patches & smash patches unless you know what you're doing. Note: some users have reported that this optional file may break certain quests that use dragons. If this occurs for you, simply disable the Force DDC Only plugin and try again. Afterwards, you can re-enable the plugin.
• Force Vanilla (ogDDC2_ForceVanillaPluginDragons_usleep3-0-3.esp): This removes all non-DDC2 dragons added by other mods, but keeps vanilla dragons. The resulting leveled lists are up-to-date with USLEEP v3.0.3 (but USLEEP is NOT required). This file must be placed at the bottom of the load order (or at least after all mods that edit dragon leveled lists). DO NOT CLEAN THIS FILE -- IT INTENTIONALLY CONTAINS "IDENTICAL TO MASTER" ENTRIES. You can use bash/smash patch to change the purpose of this file -- after patching, it will add vanilla dragons back into the leveled lists if they were deleted by another mod, but won't remove the other mod's entries.

In theory, this mod is compatible with everything. The plugin does not edit any vanilla entries, so it can't conflict in the normal sense. Because the leveled list entries are added through scripts, it will automatically fuse with other dragon mods without a patch.

There are a few caveats though:

• Encounter levels may change for dragons introduced by other mods. Due to the way leveled lists work, if the dragons from this mod and another mod are added to the same list but at non-matching levels, the will conflict with each other. To resolve this, any non-matching encounter levels will be adjusted.
• More than 255 entries in leveled lists is impossible. You have complete control over the number of entries added by my mod through the MCM, so if you have a lot of entries already, just switch to "One-To-One" mode and maybe disable some dragons that you don't like.
• Dragon combat changes, such as those introduced by DD and DCO, may or may not apply to my dragons. Some changes might apply, some changes might not. The combat changes will definitely still apply to vanilla dragons though, so the mods are compatible with each other. Update: there is now a patch for DD. Testing seems to indicate that DCO's changes all apply to my dragons automatically.
• Script-added dragons would conflict with this mod. However, I don't know of any other mod that adds dragons through scripts other than mine.
• Script-bloated playthroughs are going to be buggy even without my mod. Since this mod relies on scripts, if you have a playthrough that's already experiencing bugs related to script bloating (and especially unsafe scripts), this might prevent my mod from functioning.

Is this compatible with x? Please see compatibility section.

Can you add an Enderal version? I don't use Enderal, so I can't. But if someone else wants to build a patch I would allow it.

I don't like x dragon, can you get remove it? You can already! Check out the MCM menu.

How is this different from x dragon mod? In concept, the most similar mod is Chaos Dragons. See points 1, 2, and 4 of the overview for big conceptual differences with CD. As far as content is concerned, it shares a handful of dragons with CD, and many more dragons were designed using resources from CD. But there are also quite a few dragons that aren't from CD, and many of the modified ones are probably unrecognizable. Other dragon mods, such as Deadly Dragons or Elemental Dragons, are actually not very similar.

What are their abilities? Check out the excel spreadsheet under Misc. downloads, and also this reddit comment.

Can I ride the dragons? I've tested Bend Will on some of the dragons and it worked. Hopefully they all do.

I killed a dragon and it didn't give me a soul. MCM-spawned dragons will never give a soul. Console-spawned dragons will only give soul if you choose the right version of the dragon. Actual dragon encounters will give you a soul. If it doesn't, there could be a variety of problems, none of which is related to my mod (which doesn't edit the soul absorption mechanic in any way). Examples: script lag or this.

Crash Fixes is reporting an error when your dragons appear. Go to your CrashFixPlugin.ini and change the "UseOSAllocators" setting back to its default value of 0. (Some users say the mod runs fine with OS Allocation enabled, so I suggest testing the mod before you tinker with your settings.)

Are there any bugs? If you're using the No Plugin Dragons optional file, certain dragon-related quests might fail. If you encounter this problem, disable the optional file and try the quest again. After completing the quest you can re-enable the optional file. Other than that, there is only one minor graphical bug: some of the dragon meshes do not animate correctly when their soul is absorbed, but this does not effect gameplay at all. If you find any other bugs (and they're actually caused by my mod), please report them so that they can be fixed.

Are the scripts safe? Yes, the scripts do not contain any RegisterForUpdate() calls and are thoroughly tested. There are currently only 2 added scripts: the MCM/installer script which only runs when loading Skyrim or when using the MCM menu; and the Lava Dragon's animation script, which runs only while there is a living Lava Dragon.

Is it safe to uninstall this mod? As with any mod that adds new content, you should keep a backup save from before your installation, so you can revert to that when uninstalling. However, I don't expect any issues with uninstalling mid-playthrough. If you are going to try to uninstall without reverting your save, go to a location with no dragons (alive or dead); disable the mod through the MCM menu; make a clean save; uninstall the mod; load and make a clean save again.

Should I uninstall DDC1 before installing DDC2? It's up to you. DDC2 will treat DDC1 as just a regular dragon mod, so you would get the new dragons in addition to the old dragons. Most of the old dragons are in the new one, but many of them have new textures and abilities. So if you don't mind a bit of redundancy, you can keep DDC1 installed, but you can also remove it to reduce your load order, or swap it out for another dragon mod. (Just keep in mind Skyrim's general uninstalling rules. DDC is pretty safe for uninstallation, but it's always safer to revert to an old save or start a new one.)

Do you have permission to use <some mod author>'s assets? Yes.

Can I use your assets? Many of these assets belong to other authors. You are welcome to use assets created by me, as long as you give me credit. However, if you use assets that were partly or entirely made by another author, you MUST have that other author's permission prior to use. Detailed authorship info is included in the Readme.

Overview
This version is very limited, and most of the information above is not accurate if you're using this version. That's because many of the things this mod does are virtually impossible without SkyUI/SKSE. I highly recommend just installing SkyUI. (If you really want the old interface, just use SkyUI-Away).

Limitations
This version does include all of the dragons, however they will only be applied to the main leveled list, not the quest leveled lists or the DLC ones. So there will still be a lot of situations where my dragons can't appear.
It is still technically compatible with every mod, however if your other mods use encounter levels that don't match the vanilla ones, they won't cooperate very well -- in that situation, your game will switch back and forth between my dragon's and the other mod's dragons, depending on your level.
Lastly, and most obviously, you won't be able to configure any of the settings (disabling certain dragons, adjusting difficulty, etc) unless you know how to edit the mod using TES5Edit or the Creation Kit.

Manual Installation: Extract all files into your /Skyrim/Data/ directory. Enable the .ESP file in SkyrimLauncher -> Data Files. Load your game, immediately create a new save, then immediately load that new save.
MO or NMM: Install it and enable it. Load your game, immediately create a new save, then immediately load that new save.
You currently don't need the hotfix for this version (it fixes things that aren't in this version in the first place).

Meshes: yousukeve, Zerofrost, Madcat221, opusGlass
Textures: Bellyache (wrig675), yousukeve, Zerofrost, digitalLion, Versispellis, Aipex8, luddeman, opusGlass
ESP content & scripts: opusGlass

Helpful dragon texture template: LoginToDownload

Deadly Dragons Patch: Mur4s4me, euphoricknave

Video: DonProtein
Screenshots: fiszi
Testing: DonProtein, fiszi

Detailed authorship info can be found in the Readme.