• Frieza Race, Female Buu Race, or Namekians are choice races, in that order. These races interact in some fashion with stamina.
  
  
• "I've been saving this. Kaioken!" is the super soul of choice, and is optimal for most Kaioken builds. This super soul is DLC only.
  
  
• Transforming from your base form directly into the various levels of Kaioken drains less stamina to maintain the form.
  
  
• Stamina drain persists through everything, including melee combat, super/ultimate moves, movement/dashing, etc, and will override your normal stamina regen. Some skills or passives interact in interesting ways, which is outlined below.
  
  
• Exact numbers for buffs and stamina use are in a section below.

There are two readily apparent schools of thought on how to use this awakening:

1. The way it's intended is as a burst of power, and some setups will cater to that more. Once active, you should use it to break the rules of the stamina attrition game, and dominate the fight as hard and quickly as you can. At a certain point, you have to decide whether you want to go forward with a final burst of damage, or release the awakening and recover stamina however you can for round 2. Likewise, you can activate it for this purpose if you already hold a stamina advantage on your opponent in order to press them for a stamina break, but this is an advanced use of the awakening, and requires a lot of experience in close combat.

2. The second way is as a lesser buff and more efficient stamina use over the course of an entire fight. You still need to keep your stamina in mind, but you aren't working against a clock if you obtain the right things you need to make a sustainable Kaioken, or Kaioken x3. Don't get into the habit of overextending yourself even though you've trained your body to sustain lesser levels. If you get in a tough spot and don't have enough stamina to vanish, you can end up in an even worse situation than a stamina break, where your stamina has no chance of coming back unless the combo drops and you release your Kaioken.
I would like to note that this method of use is, as of update 1.15, high risk for little reward. There is little advantage to using Kaioken over Potential Unleashed or your race-specific transformation unless you're coupling it with very specific skills or a playstyle that will quickly become predictable in player vs. player matches.

Buffs:
Kaioken: 1 Ki minimum, +2.5% damage (all), +5% speed (ground/fly/boost), -25% stamina cost (Vanishing, Burst Dash, Any Supers/Ultimates that have a stamina drain mechanic)

Kaioken X3: 3 Ki minimum, +7.5% damage (all), +10% damage received, +10% speed (ground/boost), +20% speed(fly), -50% stamina cost

Kaioken X20: 5 Ki minimum, +15% damage (all), +30% damage received, +15% speed (ground), +25% speed (fly/boost), -100% stamina cost



Below are drain rates WITH the Super Soul "I've been saving this. Kaioken!"

>From base form directly into all Kaioken levels:

Kaioken: Regen +1 stamina bar per 28 seconds.

Kaioken x3: Negate drain.

Kaioken x20: -1 stamina per 5 seconds.



>Progressive levels from Kaioken:

Starting in Kaioken: +1 stamina bar per 28 seconds

THEN Kaioken x3: -1 stamina per 28 seconds.

THEN Kaioken x20: -1 stamina per 3 seconds.



>Progressive from Kaioken x3:

Starting in Kaioken x3: No drain

THEN Kaioken x20: -1 Stamina every 4.5 seconds

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Stamina drain/management:

A good grip of basic stamina management is helpful for using Kaioken. Things cost less stamina, but you're gaining less too. That's where racial passives and moves like Rise to Action come into play. Time your vanishes carefully to avoid back attacks, and don't fall into the habit of spamming them just because they're cheaper. Kaioken gives you an edge in the Stamina race, but only if you use it wisely.

As mentioned above, progressive stages of Kaioken drain more stamina than going straight into x3 or x20 Kaioken. Transforming FROM Kaioken INTO Kaioken x3 will drain more stamina in the higher level. Same thing happens again with Kaioken x3 into x20, the increase in stamina drain stacking.

What this means, in short, is that you're better off starting in whatever level of Kaioken you want. Failing that, release your awakening skill and reactivate it to prevent this stacking drain effect. Thankfully, you have a 1 ki buffer zone between each level of Kaioken, but I've had to burn up some Ki to activate the level I want quite often.

If you're getting low on stamina, RELEASE YOUR KAIOKEN. The extra damage, speed, and stamina cost reductions aren't worth getting locked into a combo and not having any stamina regen. Same goes for any transformation with Ki/Stamina drawbacks. If you aren't at an advantage or are getting low on resources, release your awakening skill and get things under control before transforming again.

Frieza Race regenerates stamina during combat when executing normal melee attacks. So while performing melee attacks...

Base form: +1 stamina per 15 seconds of offensive combat.

*"Been saving this." + Kaioken: +1 stamina/8 seconds.

Soul + Kaioken x3: +1 stamina/13 seconds.

Soul + Kaioken x3 + Fighting Pose J: +1 stamina/11 seconds. (Fighting pose only active for 10 seconds by default. Fighting Pose J is also explained in the Skills Interaction section below.)

Soul + Kaioken x20: -1 stamina/8 seconds

Soul + Kaioken x20 + Fighting Pose J: -1 stamina/10 seconds

Namekians get an always active stamina regen bonus roughly equal to a stamina regen XL Super Soul effect as long as their feet are touching the ground. This does not apply while Kaioken is active, meaning it doesn't lessen the drain at all. A Namekian would be able to recover slightly faster after disabling Kaioken, but that's about it.

Female Majin have a shorter stamina break duration and recover twice as fast after their stamina is broken, allowing for high-risk Kaioken x20 gameplay with lesser drawbacks. Couple this trait with Neo Tri Beam or Final Explosion and you could easily maximize the damage those abilities have without the slow recovery they normally force upon you.

Certainly worth noting that the Majin's normal stamina recovery rate is less than other races, and that the males need to maintain above 2 stamina bars to effectively reduce damage with their passive. As such, male majin are unsuited to Kaioken builds, and female majin are pretty geared toward the 'burst' style. Couples well with "I like you better when you're mad!", which restores ki if you let your stamina deplete and causes broken stamina to regen faster.

Earthlings get extra normal melee attack power at full Ki. Again, caters to the 'burst' style more. Get max ki, Kaioken x20, and get on with the beatdown, then finish with whatever ult you want. Disable Kaioken or recover your broken stamina. Rinse, wash, repeat.

Skills:

Rest in piece, Stamina Restoration. Kaioken no longer allows you to restore your stamina while it's active at any level. If you use any stam restoration skills, it will have to be after deactivating the awoken skill.

Rise to Action:
1 Ki, 1 second activation, +1.5 stamina. Easily a go-to. Use this after a knockback or the end of a combo. Nice and straightforward.

Charged Ki Wave:
1 Ki, Near instant activation, +1 stamina, +0.5 on subsequent uses
Additional Inputs return less stamina, but do not cost additional Ki. Effective, but difficult to work into combat easily. May be useful for a quick 1 bar regen if you're capped at max ki and able to teleport to your target with your next super.

Super Drain:
1Ki, Requires target, +1.75 Stamina, -2 enemy stamina.
Pretty sweet if you're focusing specifically on the stamina struggle between you and your target. Can sometimes be more helpful than a stamina break if you zero out your target's stamina with it.
Takes practice to land, can't be used after a combo knocks your target down or away. Listen for a 'heavier' sounding hit to know when the grab won't land. You can do a light dash attack, then grab. Or find a portion of your combo that has more recovery frames for your target and grab before you land a strike that will knock them down/away. Obviously, beware of vanishes. Get predictable with this and you're done for. Justice Rush can be interrupted with a Drain grab as well.

Hyper Drain:
1 Ki, Requires target, +1.5 Stamina, +2Ki, -1 enemy stamina, -2 enemy Ki.
Pays for itself and then some. Free bar of Ki, free stamina. Drains your target quite a bit. Pretty cruel, to be honest. Same info from Super Drain applies with landing it. Note that it drains 1 less stamina from your target. Follow up with Rise to Action for additional stamina recovery at, essentially, no cost to ki.

Fighting Pose J:
1 Ki, 1.5 second activation, +50% stamina regen rate, lasts 10 seconds
Sounds great, but coupled with Kaioken, it seems to affect your -new- stamina regen rate rather than your base rate. This means that Kaioken reduces the bonus this skill provides. Does not buff stamina gained from other skills. Can be extended with DLC Skill 'Meditate' to 30 seconds.


Some supers and ultimates use Stamina as a resource to extend or modify the ultimate's functionality.

Neo Tri Beam:
3 Ki, 1 Stamina per additional shot. Max 11 shots.
Stamina cost for extra shots is reduced by 25%, 50%, and 100% per level of Kaioken Firing 6 to 9 shots will cause you to be locked into a recovery animation for about half a second. Recovery time increases to 3.5 seconds at 10 and 11 shots. Optimal amount of shots is 5 for no (0.1 second) recovery, 9 for damage with minimal recovery, and 11 for maximum damage if the extra damage will finish your foe off.
If you run out of stamina while the skill is in use, your stamina will break, but you will not be locked into a recovery animation. It's minor, but you actually regenerate stamina during it's use if using "Been saving this." even when stamina drain would normally be negated (as is the case with Kaioken x3). NTB seems to lessen the drain somehow? If you pace the beams, you can actually squeeze out a couple of extra while in x3. I've used this to assist allies who've been stamina broken in parallel quests.

One-Handed Kamehameha/OHK Mk. II:
3 Ki, 3 Stamina if used while being hit.
Mk. II costs 4 Ki and can be powered up for 1 additional Ki.
These moves will also fire without the backflip invulnerability frames if used after a knockback/down. Stamina cost when used as an evasive is reduced by Kaioken. This move has been buffed recently and can be extremely useful! Video in the credits section.

Final Explosion:
3 Ki, Maintained by holding button down, fast stamina drain. Recovery animation after move is finished.
Stamina cost not reduced by Kaioken, but depleting your stamina will break your stamina and cancel the statue recovery animation.

DLC Supers:
There are three supers from DLC Extra Pack 4 that give you Broly and Gogeta's skills from the Broly Movie. Broly's skills can be used while being damaged and, if you do so, Kaioken will negate a percentage of stamina use. One of Gogeta's skills uses stamina as well.

Gigantic Rage:
2 Ki, 3 Stamina if used while being hit. Close range grab, brings opponent down to ground level and slams them around. Satisfying. Cannot be used mid combo, difficult to follow up with most attacks.

Gigantic Charge:
2 Ki, 3 Stamina if used while being hit. Charges straight forward, no tracking. Fully charge to put opponent in stamina break status with an unblockable charge.

Powered Shell:
1 Ki, 3 Stamina if used while being hit, and will put up a barrier in this case. No barrier if used normally. Can be fired behind you if the situation requires. Tricky timing to fire behind, experiment in training.

Assault Vanish:
1 Ki, 1 Stamina. Basically a reliable instant transmission directly to opponent. Hold the button to disappear for longer and reappear where you were. Useful for dodging many things, but does not last long enough to dodge maintained beam ults or Peeler Storm, for instance. Can be used while boost dashing.


Note: I'd recommend picking an evasive that only uses 2 stamina. You can outpace your opponents for the most part, but some of the 2 stam cost evasives are pretty good. Dragon Burn does well at negating damage as well as applying a vanishable stun if the enemy touches you during it.

Super Souls:

Recommended all-rounder:
"I've been saving this. Kaioken!"
Basically a better version of other options rolled into one. Grants get Stamina Regen M, as well as a +10% to normal attacks and +20% combat Ki regen (which stacks with Divinity Unleashed's bonus, by the way. Any buff, transformation, and super soul combo should stack. Two of the same buff do not stack together. SOME buffs can be combined, and the one you last used will determine how long both effects last. Meditation can be used to get max Ki and extend the duration of Data Input, for instance).

To obtain "I've been saving this. Kaioken!" Super Soul, you must own DLC Pack 1. PQ 103 drops it. You must fight through the quest until you fight SSGSS Goku for the first time. If you beat him, you should get a message saying "Got Equip". If you don't get that message, you will have to restart/try again.

"Been saving this." does not buff stamina gained through Rise to Action or other Stamina regen skills. Only the passive regen rate.

Decent second option for burst playstyle or non-dlc players:
"Body, don't let me down!"
Goku's super soul. Boosts Normal Attacks L (15%), but drains health. Buff/debuff is the same for all levels of Kaioken, which grants a potential 22.5% boost to normal attacks, a 7.5% boost to all other damage, but at the risk of taking increased damage to a rapidly depleting health bar. VERY situationally useful, such as turning the tables after recovering from a stamina break last minute in an online match. Obviously works best on a combo build. A human at max Ki would have their damage buffed further. DEFINITELY for the 'burst damage' method of using Kaioken, and possibly better, depending on your playstyle (or if you just want to disrespect your enemy). Watch that health, though.

Complete dud:
"I'll kill all of you!":
Dodoria's Super Soul, shouldn't be used unless patched. It gives the same Stam Regen M bonus at max Ki, but for some reason it doesn't seem to negate Kaioken x3 stamina drain once ki is full after transforming. It will slow stamina drain at Kaioken x20 if it's activated with full ki, but not as much as "I've been saving this. Kaioken!" does. Drain for "I'll kill all of you!" clocks in at 1 stamina drain/4 seconds at Kaioken x20. Basically a poor man's "I've been saving this. Kaioken!" for those that don't have this SS, or who do not own DLC1 yet. You'd probably be better off selecting another SS in the meantime, unless you're just going for slightly longer Kaioken rather than a damage boost with self health drain.
(This may be a typo in the SS. It feels more like Stam Regen S.)

Kaioken buff numbers were taken from this topic by MGOStealth:
Details on buff numbers for other transformations and moves can be found there.
https://steamproxy.net/sharedfiles/filedetails/?id=826723770


One-Handed Kamehameha Mk. II Buffed:
Tobirama TV does an excellent job of displaying the recent changes to OHK Mk. II that make it extremely useful on its own, let alone coupled with the information of this guide.
https://youtu.be/qqlUZX7AZOQ

Thanks to Giantmeme for asking about "Body, don't let me down!" super soul!
Thanks to jackoftrades222 for prompting testing on "That heat, I'll have to match it!" and other new DLC super souls!

2/2/2018
-Added tidbits about Majin race
-Updated info about acquiring Super Soul "I've been saving this. Kaioken!"
-Ki cost for additional input for One-Handed Kamehameha Mk.II updated from 1 Ki to 3 Ki, for 6 Ki total cost.

11/1/2019
-Updated for changes in various skills, DLC, and mechanic changes.

9/5/2020
-Updates to Kaioken from patch 1.15. Stamina regen blocked while Kaioken is active.
-Updated various info, including adding Earthling to race section and amending Namekian info.