Across
1. AN ELF (also acceptable, with 1-Down: CUPID/COAL, COMET/CHIA, VIXEN/VASE, STAFF/SLED)
2. RED
3. HOLLY
4. SANTA
5. MASS (theoretically acceptable: ALPS and LAOS)
Down
1. A TOY (see 1-Across)
2. MR. CLAUS!
3. CHRISTMAS
4. HO HO HO
5. YEOW (we'll accept YUCK and even YIKE)
6. JESUS (also acceptable: MALLS, SALES, CARDS, TV ADS, BOWLS)
Extra credit if you got 1-Across and 1-Down as intended.
Triple credit for figuring out 2-Down.