Detachment

Detachment is pretty self-explanatory for the large part, halve your max HP in order to get 3 extra mutation choices,though what isn't mentioned is the fact that it halves your HP at the moment you pick the Ultra and is not an overall passive.

Building

Detachment trades half of the max HP at the moment of pickup in exchange 3 extra mutation choices.

Other Mutations

Synergies

• Rhino Skin can greatly mitigate the downside if you avoid choosing it before picking Detachment in order to get +4 HP, putting you at 5 max HP.
• Strong Spirit can be very useful in the case you followed the previous synergy.

Similar Niches

• There no other mutation similar to this.

Anti-Synergy

• Strong Spirit can become obsolete in the case you don't have Rhino Skin as you will be unable to refresh it.
• Defensive and Offensive mutations that revolve around taking damage/being near enemies such as Sharp Teeth and Gamma Guts become even more obsolete due to the lower HP.
• Second Stomach andBloodlust become obsolete as your max HP is lowered to 1/3/5 HP, depending on how you picked Rhino Skin.

Crowns

Synergies

• There aren't any significant synergies with crowns.

Anti-Synergies

• Crown of Death is highly detrimental as it further lowers you max hp, down to the point of having 0 max HP, resulting in dying upon proceeding to the next stage.
• Crown of Destiny's downside only results in only one mutation choice per set, leading to missing out on beneficial mutations.