If a combiner combined and untapped. Would Lose the Initiative cancel the untap combiner effect?

A team of characters combining isn't actually untapping; the resulting Combiner character is entering the battlefield untapped (like all characters which enter the battlefield after the start of the game, unless another card or ability says otherwise).

Source: Wizards of the Coast (2020-06-10)    【Link to Ruling】

Tags: Lose the Initiative, Combiner

I couldnt find this having been asked before - if Marksmanship is played against a Combiner - does this do the 2 damage? Are Combiners in bot mode?
Combiner mode is not the same as bot mode, so Marksmanship would not do 2 damage.

Source: Wizards of the Coast (2019-04-12)    【Link to Ruling】

Tags: Marksmanship, Combiner

Some cards refer to Autobots or Decepticons. How do I know which characters are Autobots?

Autobots have a red frame and the Autobot insignia in the lower right corner. Decepticons have a purple frame and the Decepticon insignia in the lower right corner. A few characters have "Autobot" or "Decepticon" in their names, although these aren’t the only Autobots and Decepticons.

Source: Wizards of the Coast (2018-10-11)    【Link to Ruling】

Tags: Autobot, Decepticon

When you play an Enigma of Combination to combine and all characters are in bot mode, do you also get to do the other text on the Enigma such as drawing 2 cards when you play the Stunticon Enigma, or do you only get that effect if you play the Stunticon Enigma once Menasor has already been formed?

You perform the actions on the card in the order that they’re written, which dictates when effects are applicable to a given scenario. For example, if you’ve already played an Enigma to combine, you would receive the top bonus.

Source: Wizards of the Coast (2019-02-01)    【Link to Ruling】

Tags: Combiner

Furthermore, can a Power Sword be transferred if the combined form is not Melee?

Yes.

Source: Wizards of the Coast (2019-02-01)    【Link to Ruling】

Tags: Combiner

If the Combiner is treated like a new character upon combination, will Armed Hovercraft activate if moved from a composite part to the Combiner upon combination?

No. It would stay attached, but would not activate upon combination.

Source: Wizards of the Coast (2019-02-01)    【Link to Ruling】

Tags: Combiner

When I play Brainstorm, Heat of Battle, then the Combiner Enigma, do all of my combiners get the BOLD 3 so therefore my Combined Combiner gets all of the BOLD stacked?

“Sadly, yes.” - Rules Master Matt Tabak.

Source: Wizards of the Coast (2019-06-07)    【Link to Ruling】

Tags: Combiner

Is keeping a weapon, armor, and utility a feature of combining or is it based on an action?

It’s a feature of combining. Combiners have one of each slot unless otherwise specified.

Source: Wizards of the Coast (2019-02-18)    【Link to Ruling】

Tags: Combiner

With the some of the new combiner teams being over 25 points, how does this work? Do the players decide on the points totals they’ll be playing or are you still only able to take 25 points and you’ll not be able to use this team to combine?

In a normal game, you must still adhere to the 25-star limit when building your deck, but Optimus Maximus and Volcanicus have special rules on their cards that explain how they function with more than 25 stars.

Source: Wizards of the Coast (2019-03-08)    【Link to Ruling】

Tags: Combiner

The enigma cards state that all the of the combiner component characters must be “in bot mode on the battlefield and/or in your KO area”. Do they still have to be in bot mode if they are in the KO area? Given how Volcanicus is formed I assumed they could be in alt mode, but now that the new rules state you can flip characters in the KO area, I’m not so sure.

Yes.

Source: Wizards of the Coast (2019-03-08)    【Link to Ruling】

Tags: Combiner

When a Combiner combines and the upgrades on its components go onto it, does that count as putting it on a character in the same way that Swap Parts does? For example: Torox has Energon Slingshot before Predacon Enigma was played. When Predaking is combined into, will Slingshot count as being put on a melee character and have its ability to deal 1 damage activate?

No. Upgrades are not “put on” when Combining, they are “kept on”.

Source: Wizards of the Coast (2019-03-08)    【Link to Ruling】

Tags: Combiner

What are Combiners?

It would be hard to have a set called Rise of the Combiners without… the Combiners!
Combiners are teams of characters that join in a third mode called Combiner mode. Most teams have a corresponding battle card called an Enigma that combines the team under the right circumstances. One Combiner in this set (Dreadwing - Sky Destroyer) has a different way of combining.
When a character is combined, it starts untapped and it gets all the damage counters from the characters that formed it. It can keep upgrades from those characters based on its upgrade slots. Unless the Combiner says differently, it will have 1 Weapon slot, 1 Utility slot, and 1 Armor slot like most characters. If there are too many Upgrades to fit into a slot, you can keep as many as you can fit, and the rest are scrapped.
A character in Combiner mode is a single character, even though it’s made up of multiple cards. When it attacks, the whole thing becomes tapped. If it’s KO’d (and somehow you haven’t lost the game), it stays in Combiner mode in the KO area.
A character in Combiner mode can’t flip. Ignore any instruction to flip it. Also, a character in Combiner mode can’t “break apart” into its individual cards.

Source: Wizards of the Coast (2019-03-01)    【Link to Ruling】

Tags: Combiner

Let's say you have a team of combiners. And your opponent’s characters are all tapped out. You have one character untapped and all of your characters are in bot mode. I know you can’t use Inferno Breath in this instance because you wouldn’t be able to attack to end the turn. However, if you play Brainstorm and then play Inferno Breath, tapping your last character and then using the Brainstorm’s second effect to play and enigma and combine, is that a legal play?

In this scenario, you actually could play Inferno Breath because you can tap your last character. When it comes time to attack, if you have no untapped characters, your turn would end. If your opponent also has no untapped character, you would untap all characters as usual and your opponent’s turn would begin. If you play the enigma and combine your characters into a Combiner, the Combiner begins untapped, so it would be the character that attacks.

Source: Wizards of the Coast (2019-04-01)    【Link to Ruling】

Tags: Combiner

Are Combiners able to flip to their separate alt modes once they are combined?

Currently there is no way to flip a Combiner once it is combined.

Source: Wizards of the Coast (2019-01-25)    【Link to Ruling】

Tags: Combiner

If a combiner is KO'd, do each of its individual components get put into the KO space, or does it stay a combiner? If it's the components, do they get KO'd in bot mode?

It is KO’d in combiner mode. That is generally the end of the game, but in corner cases like Volcanicus and REDACTED this can come up.

Source: Wizards of the Coast (2019-02-11)    【Link to Ruling】

Tags: Combiner, KO