save, rescue, protect
Easy
There is no direct antonym because not doing an action is not the opposite. However, the opposite of redo (like repeat) might be to abandon, leave alone, stop, or quit.
They are directly opposite, Construct means to build and destruct means to destroy.
The opposite of preserve could be destroy or consume. The opposite of preserving food could be consuming and/or wasting it.
Not all - these words opposite in meaning - create means to make something appear- annihilate means to reduce to nothing, destroy.
The opposite of create can be destroy, undo, or cancel.Words like destroy are spoil, ruin, wreck, kill, or annihilate.
An opposite of the word embellish could be simplify.
Cluster means a close grouping of things, so yes it would be considered an antonym. Words it is opposite of would be: one, singular, etc.
save
Retain
The task(s) were to seek out and destroy the enemy; almost (no nuclear weapons) by any means available.
diminish, destroy