Diamond Knight (5e Creature)
From D&D Wiki
Medium construct, unaligned
Antimagic Susceptibility. Diamond knights are incapacitated while in the area of an antimagic field. If targeted by dispel magic, it must succeed on a Constitution saving throw against the caster's spell save DC or fall unconscious for 1 minute.
Diamond Spear. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 7/9 (1d8/1d10 + 3) Slashing damage.
Spear Gore. (Recharge 1d6+2 Turns) Melee Weapon Attack: +3 to hit, reach 20 ft. Line, one target. Hit: 7/9 (1d10 + 3) Piercing damage.
Diamond knights are one of the four suit related creatures, the others being heart clerics, club bashers, and spade rogues. They exist as minions to the people that summon them and take on traits that their masters have. If a diamond knight's summoner is killed or the summoner relinquishes their control over them, they wander the lands in search of new meaning. Sadly, since they are made out of a very flammable, dissolvable, and all-around destroyable substance, it is borderline impossible to find a diamond knight being hospitalized or finding one in the wilds. When they wish to, they can summon a weapon made out of playing cards made of the suit of that creature. In particular, diamond knights can summon a diamond spear, a long, tri-tip spear that can gore enemies.