How explicit is the rule Balrog where it is says Ringwraith

[rezwits]

This is kinda stupid but how explicit is the rule:

Whenever a card or rule says the word Ringwraith it also applies to Balrog characters and players.
Whenever a card or rule says the word Wizard it also applies to Fallen-Wizard characters and players.

Now I understand if there are "Specific rules that clearly state Balrog characters/players do blah blah, or Fallen-Wizard characters/players do blah blah etc, they override.

But is this just a serious blanket case? Where no matter what, if you see Ringwraith, it's also Balrog? if you see Wizard it's also Fallen-Wizard?

Example
20. A character in a Ringwraith's company has a roll modified +2, for a check

Thanks

[Konrad Klar]

But is this just a serious blanket case? Where no matter what, if you see Ringwraith, it's also Balrog? if you see Wizard it's also Fallen-Wizard?

Whenever a card or rule says the word ABC it also applies to the XYZ does not mean that vice-versa. What applies to XYZ not necessarily applies to ABC.

Example
20. A character in a Ringwraith's company has a roll modified +2, for a check

A Balrog player acts as a Ringwraith player. Any card and rules text applying to a
Ringwraith also applies to The Balrog (e.g., if a card refers to a Ringwraith, it now
applies to “a Ringwraith or The Balrog”).
However, instead of using the special rules listed on page 59 of the MELE rules (or
wherever else these rules may appear), a Balrog player uses the following special
rules:
• Any ring in The Balrog’s company at the beginning of the end-of-turn phase is
automatically tested. Any ring test in The Balrog’s company has a modification
of -2.
• The Balrog may carry items (including rings) but may not use them (i.e., an item
has no effect on The Balrog’s company or on his attributes and abilities).
• The Balrog never makes corruption checks and corruption cards may not be
played on The Balrog.
• Normally, The Balrog may not use starter and region movement (as stated on his
card). However, the play of certain resources can expand his movement capabilities.
• The Balrog’s company is always overt.

Some rules, that refer to Balrog (Fallen-wizard) specifically may supersede other, that refer to Ringwraith (Wizard).

Other example (a card's effect [limitation] that applies to Ringwraith character, but not to the Balrog):

Any minion company without a Ringwraith may attack another minion company without a Ringwraith. The attacking company may contain The Balrog. Discard when any play deck is exhausted. Cannot be duplicated. The ranks of the orcs had opened, and they crowded away, as if they themselves were afraid.-LotRII

Another example (a card that affects both Wizard and Fallen-wizard, but has different effect on one, and different on other):

Corruption. Playable on a Wizard or a Fallen-wizard. He receives 1 corruption point (CP). If he is a Fallen-wizard, he receives 2 stage points and the CPs received are instead: 4 CPs if his stage points (SPs) exceed 18, 3 CPs if his SPs exceed 11, 2 CPs if his SPs exceed 5, 1 CP if his SPs exceed 0 (use the first that applies). The target makes a corruption check whenever his controlling player plays a stage card. Cannot be duplicated on a given character. During his organization phase, target may tap to attempt to remove this card. Make a roll-if this result is greater than 6, discard this card.

So if it comes to rules, you must know Balrog (Fallen-wizard) rules before you will try to apply to them a rules that affect Ringwraith (Wizard).
There is a possibility that some of them have been superseded by rules that affect a Balrog (Fallen-wizard) specifically.

[rezwits]

Too bad this is bad, fix for the game, because it's not a overall case.

We have to completely go over these:

Latest Rule Book or Combination there of (Balrog, LE, Wizards, etc)
Rules Inserts for any specific Expansion
CRF
CoL Tournament Policy
NetRep Digests
CoE Errata

To find every nuance. Which is ok. NP, thanks again.

[Konrad Klar]

Latest Rule Book or Combination there of (Balrog, LE, Wizards, etc)
Rules Inserts for any specific Expansion

The first includes the second.
And AFIK a Rules Inserts for Fallen-Wizard and Balrog are only ones that contain rules that supersede general rules for Wizard and Ringwraith.

Rest of this list are things that you should know if you want to have your knowledge about rules up to date (whether you play as/against Balrog, or Fallen-Wizard, or not).

For the other hand you can play cards affecting Ringwraith (Wizard) against/for Balrog (Fallen-Wizard) safely. Unless text of particular card states otherwise, there is 1:1 translation between references from Ringwraith to Balrog and from Wizard to Fallen-Wizard.