The Magic Flute solution
by Kegler
As suggested by 26 Across, THE PIED PIPER, a “RAT” has been removed from each of fifteen entries.
Across
| 1 | P + ROBE |  
| 5 | R(ATHE)R (HEAT anag) |  
| 8 | COAL ("COLE" hom) |  
| 12 | M(O)IET + Y (TIME anag) |  
| 14 | ER(RAT)A |  
| 15 | E + RNS |  
| 16 | SE(G)AL |  
| 17 | CELEBRATES (BEETLE CARS anag) |  
| 19 | BER + ATES (REB rev; EAST anag) |  
| 20 | S + HOT |  
| 22 | SE(T)H |  
| 25 | ORATED (TO DEAR anag) |  
| 26 | THE PIED PIPER |  
| 29 | L(I + QUID + DIE)T |  
| 31 | WAL(NU)T |  
| 32 | R(A + TIme)ON'S |  
| 33 | AN(I + SEE)D |  
| 36 | ORGAN (ORANG anag) |  
| 39 | NARRATES (rev hidden) |  
| 41 | R(A + D)IUM (MUIR rev) |  
| 42 | AND + ROID (rev) |  
| 43 | O + PEN |  
| 44 | NA(K)ED (DEAN rev) |  
| 45 | CAST + RATING |  
 
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Down
| 1 | P(IR)ATES |  
| 2 | O + SAGES |  
| 3 | B + REASTPIN (PAINTERS anag) |  
| 4 | EAR(L)S |  
| 5 | H + ON + CHO |  
| 6 | EMS (odd letters) |  
| 7 | ROLLTOP (TROLLOP anag) |  
| 8 | CITRATES (IT REACTS anag) |  
| 9 | ATM (1st letters, &lit) |  
| 10 | LYRATE (REALTY anag) |  
| 11 | BREECH ("BREACH" hom) |  
| 13 | EM + BED (ME rev) |  
| 18 | SHOR(TEN)ING |  
| 19 | BOy + T(SWAN)AN |  
| 21 | gOLDIE |  
| 23 | T(R)EES |  
| 24 | PRATIQUE (QUIT PER A anag) |  
| 27 | PRA[T/y]ING |  
| 28 | BAN + AN + A |  
| 30 | DI(OD)ES |  
| 34 | SERRA + TE |  
| 35 | ERRAT(I)C (CRATER anag) |  
| 37 | R(I)OT |  
| 38 | AMEN (NAME anag) |  
| 40 | SOD (rev) |  
 
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