Flying

Threshold — As long as seven or more cards are in your graveyard, Boneshard Slasher gets +2/+2 and has "When Boneshard Slasher becomes the target of a spell or ability, sacrifice it."

Marauding Boneslasher can't block unless you control another Zombie.

Sacrifice an artifact: Regenerate Rusted Slasher.

At the beginning of combat on your turn, target creature you control gets +2/+0 and gains trample and haste until end of turn.

Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Deathtouch

Whenever Unstoppable Slasher deals combat damage to a player, they lose half their life, rounded up.

When Unstoppable Slasher dies, if it had no counters on it, return it to the battlefield tapped under its owner's control with two stun counters on it.

Menace (This creature can't be blocked except by two or more creatures.)

Whenever War-Trained Slasher attacks a battle, double its power until end of turn.