...The Harder They Fall

...The Harder They Fall is a trophy in Fallout 4.

Requirements
Kill five giant creatures. The only two enemies that count for this trophy are super mutant behemoths and mirelurk queens.

If you are travelling with a companion, you must be the one to fire the killing shot in order for it to count towards the trophy.

Super mutant behemoths

 * Outside of Fort Strong.
 * West of Natick Banks.
 * West of the Suffolk County charter school.
 * South of Walden Pond at a playground.
 * Swan is a unique super mutant behemoth and can be found at Swan's Pond.

Mirelurk queens

 * At the Castle as part of the quest Taking Independence.
 * At the Murkwater construction site, must be defeated in order to use the area for settlement.
 * Spawns at Spectacle Island once throwing the circuit breaker.
 * At Nahant Chapel, nesting near the coast.
 * In the basement of the Massachusetts State House.

Bugs
Progress towards the trophy may be awarded when an NPC kills a behemoth without the player having to do anything.

Trophy will not unlock at times even with previously killing swan, went back to swans corpse resurrected via console. Killed Swan again and achievement unlocked.