The Bona Mors devotion is an important one, indeed the most important, in a certain sense: there's little point in so mismanaging one's affairs as to spurn God's grace and die the death of the wicked, after all.
Saints of God, come to our aid! Luckily enough, Miss Medieval-Liturgy-Mystic, St Gertrude the Great, had a revelation (see her Revelations, IV, 11) from St Benedict, the glorious Patriarch of Monks, that whoso would frequently invoke him, devoutly recalling and reminding him of his most blessed death (undergone while he stood praying in his monastery's oratory – see St Gregory the Great's account in his Dialogues, II, 37), would obtain his assistance at the hour of death and defence against Satan's final attacks: tit for tat. Some monasteries therefore used the following prayer in his honour after Compline (the anthem is from St Gregory's account, the collect alludes to St Gertrude's vision), and when I get around to it so do I. Ye ne'er can tell...
Ant. Stans in Oratorio dilectus Domini Benedictus, Corpore et Sanguine dominico munitus, inter discipulorum manus imbecillia membra sustentans, erectis in cœlum manibus, inter verba orationis spiritum efflavit, qui per viam stratam palliis et innumeris coruscam lampadibus cœlum ascendere visus est.
V/. Gloriosus apparuisti in conspectu Domini.
R/. Propterea decorum induit te Dominus.
Deus, qui pretiosam mortem sanctissimi Patris nostri Benedicti tot tantisque privilegiis decorasti: concede quæsumus nobis; ut cujus memoriam recolimus, ejus in obitu nostro beata præsentia ab hostium muniamur insidiis. Per Christum Dominum nostrum. R/. Amen.
(Anthem. Standing in the place of Prayer, Benedict, beloved of the Lord, 'his soul' [–] strengthened by the Body and Blood of the Lord, his failing limbs upheld upon the arms of his disciples, lifted up his hands to heaven, and, while prayer was actually being offered, yielded up his soul, which 'took' [was seen to take] its heavenward course along a way all strewn with mantles and aglow with countless lights.
(V/. Renowned hast thou appeared before the Lord.
(R/. Wherefore the Lord hath surrounded thee with glory.
(Let us pray.
(O God, Who hoast enriched the precious death of our most holy Father Benedict with favours so many and so great; grant us, we beseech Thee, that he, whose memory we now recall, may protect us from all the wiles of our enemies by his blest presence in the hour of death. Through Christ our Lord. R/. Amen.)