Spells only do what they say.
Greater Restoration does not alleviate the conditions ended by Lesser Restoration, because it does not say that it alleviates the conditions ended by Lesser Restoration.
Sidenote. As GR uses a 5th level slot and only ends one effect, it wouldn't make much sense for a character to use it ahead of LR, which uses a 2nd level slot and ends one condition, to end paralysis, barring situations of one being prepared ahead of the other.
No, otherwise it would be mentioned by the spells' descriptions.
That being said, I believe the reason why it's not mentioned are the spells' intended usages / their themes.
Lesser Restoration allows you to remove the following conditions:
disease, [...] blinded, deafened, paralyzed, or poisoned
All of them are physical conditions, leading me to believe that the intent of the spell is to be your all-rounder spell for minor illnesses etc. Frightened is not a physical condition, therefore it doesn't fit the theme.
Moving on to Greater Restoration, it can remove the following effects:
- One level of exhaustion
- One effect that charmed or petrified the target
- One curse, including the target’s attunement to a cursed magic item
- Any reduction to one of the target’s ability scores
- One effect reducing the target’s hit point maximum
It removes major detrimental effects, and once again, they are all physical effects (and curses), aside from the Charmed condition. In my opinion, it would be reasonable to include Frightened alongside Charmed, but since Charmed can be way more impactful than being Frightened (in one case, you run away, in the other, you might fight for the opposing team), that's probably why they chose Charmed instead of Frightened.
In addition to the previous paragraphs, there are spells that do help against the Frightened condition (sometimes limited to against specific types), just not the Restoration spells:
- Protection from Evil and Good: immune against being Frightened (and other effects) by aberrations, celestials, elementals, fey, fiends, and undead, and advantage on saving throws for existing effects.
- Aura of Purity: advantage on saves against Frightened (and other effects)
- Heroism: immunity against the Frightened condition
- Heroes Feast: immunity against the Frightened condition
- Calm Emotions: can suppress the Frightened condition for its duration, i.e. up to 1 minute. Effect resumes afterwards, unless the duration has run out.
There are probably a few others that I failed to find.
Best Answer
Greater Restoration ends one occurrence of any effect, that it can cancel, on a creature you target. You do not need to know the specific effect.
Greater Restoration states that:
Greater Restoration does not say you need to specifically target an effect, just that you target one creature and you can then end one of those effects affecting that creature.
It also does not state that you can only end an effect that you know of, or that you must know what is effecting them. Since that the description does not specifically state that you must know what the effect is that you want to end, it would seem viable that you could end any effect that Greater Restoration is capable of ending.
Greater Restoration also says you target a creature, not an effect, meaning you don't need to know of the effect, or which specific effect it is, in order to cancel it.
For Example: Bob the Barbarian got a super cool new sword, but now he is really eager for battle and is all bloodlusty. You cast Greater Restoration on him as you think he may be cursed by the sword. Turns out the sword was not cursed, but instead another item/ability was causing this. Since that GR says it ends one of those effects, it would still successfully end the curse from a different weapon, or a charm that caused Bob to be more aggressive.
If the creature is under the effect of multiple effects, it is unclear as to which one is cancelled as the spell does not specifically state. This would be up to the DM though there are a few ways this can be handled:
Keep in mind that you can cast Greater Restoration as many times as you would like assuming you have the spell slots. If you end on effect, you think/know they are under the affects of another effect, cast it again.