SOLVED - Cryptic Pyramid IV

[Elethiomel]

1. Before wasting away, Oscar is weighing in.
2. Roughly nought kept in touch.
3. Unusual overdose defense.
4. Colorless porous cell exhibits a sign of life.
5. Before the beep, our relatively natural numbers are ringing.
6. To engulf yourself, ultimately gone.
7. Reply to earn updates without embedded software.
8. One middle rung tagged player.
9. Regarding oneself externally.
10. Modern return trip pursuing light speed.
11. Blonde features signaling failure.
12. Ten decibel rant in Indian.
13. Knowing look around and gutted top dog.
14. Engrossing tricks, upsetting foremost Chinese dynasty.
15. Grandma, let's find one of the boys.
16. Tread carefully in this line of work.
17. Every second friend is a comrade.
18. Disentangle fibers to investigate NASCAR drivers.

[Quailman]

17. RED

[Zag]

6. OFF
17. RED

[Vagrant]

11. DEFEAT
15. MALE

[Zag]

16. TRADE?

[Thok]

15 MALE (In GrandMA LEts)
4 PULSE (anagram Porous Cell - color)

[novice]

3. ODD
9. OF
13. LEADER (LE(AD)ER)
14. CONSUMING

[novice]

5. ROUNDING (ROU+N+DING)

[novice]

2. ABOUT (AB(O)UT)

[Elethiomel]

All correct so far.

[Oscar]

I couldn't let this go without weighing in:
1. O-PINING

[novice]

opining -- 1. Before wasting away, Oscar is weighing in.
about -- 2. Roughly nought kept in touch.
odd -- 3. Unusual overdose defense.
pulse -- 4. Colorless porous cell exhibits a sign of life.
rounding -- 5. Before the beep, our relatively natural numbers are ringing.
off -- 6. To engulf yourself, ultimately gone.
answer -- 7. Reply to earn updates without embedded software.
united -- 8. One middle rung tagged player.
of -- 9. Regarding oneself externally.
current -- 10. Modern return trip pursuing light speed.
defeat -- 11. Blonde features signaling failure.
brave -- 12. Ten decibel rant in Indian.
leader -- 13. Knowing look around and gutted top dog.
consuming -- 14. Engrossing tricks, upsetting foremost Chinese dynasty.
male -- 15. Grandma, let's find one of the boys.
trade -- 16. Tread carefully in this line of work.
red -- 17. Every second friend is a comrade.
card -- 18. Disentangle fibers to investigate NASCAR drivers.[/b]

[novice]

18. CARD

[novice]

12. BRAVE (10 dB = B + RAVE)

[novice]

7. ANSWER (earn anag. around sw)

[novice]

8. UNITED (knowing El, this one's probably rUNg + "IT'ED", as in "Tag, you're it")

[novice]

10. CURRENT (C+ RETURN anag.)

[novice]

DEFEAT BRAVE LEADER CONSUMING -- BEATING

[novice]

MALE TRADE RED CARD - HEART

[novice]

OPINING ABOUT ODD PULSE ROUNDING OFF -- COM(PLE)MENTING

[Thok*]

[novice]

Thanks Thok, that makes more sense.

[Zag]

I feel so out of my league. I tried all of those and only got three. At least I understand most of them once I see it, but could you explain these?

rounding -- 5. Before the beep, our relatively natural numbers are ringing.

answer -- 7. Reply to earn updates without embedded software.

united -- 8. One middle rung tagged player.
(I get all of this except for player = ed. Or is "it" being treated as a verb, so ited is the past participle?)

[novice]

[Zag]

[Oscar]

Given Elethiomel's track record I think we can assume the final clue is another &lit. One that almost works is:
THROAT
where 'thro' is archaic for 'through/thru' which at a stretch could mean complementing, plus 'A' plus 'T' as the heart of 'beating'.

It might not be the intended answer but I've seen (and written) much worse!

[Thok]

[Oscar]

Or more likely:
BREATH
Complementing 'A' = B + beating heart = REATH

Excellent!

[Zag]

Nicely done, Oscar!

Great puzzle, El, especially the final clue.

[Elethiomel]

Thanks, Zag, and to Oscar for weighing in at some critical junctures.