Which verb + ER becomes a noun? (except worker, teacher, driver, runner, swimmer, reader, painter, singer, dancer, writer, rider, player, winner)

Which verb + ER becomes a noun? (except worker, teacher, driver, runner, swimmer, reader, painter, singer, dancer, writer, rider, player, winner)

Gardener gardener farmer farmer woodcutter waiter waiter smoker
Singer singer killer murderer murderer
Thinker cleaner