Exotic Types of Monsters

I wondered, how could I sprinkle vulnerabilities and resistances onto existing monsters, while still having the originals exist, without breaking immersion too hard? The examples shown here have a weapon type triangle theme, but this principle could be applied for other type combos too. It was when Monstery Monday "Exotic" theme appeared when I realized how to keyword it.

Skeleton
Lvl 1/3 undead
10
Undead: Unliving, Undying.

The first time this dies, reset to 1 HP instead (excluding minions).

Exotic Skeleton.

Resistant to Piercing. Vulnerable to Bludgeoning.

  • Grave Arrow.
    (8ft ft)
remixed from Skeleton by NNimble Co.
Lvl 1 dungeon denizens
28
Oozes: Digestive Touch.

Contact with an ooze inflicts the Digested condition: they deal an additional X damage for each time the target has been Digested this encounter.

Oozes: Goopy.

When crit or dealt any slashing damage: summon X ooze minions (size: d6); their attacks inflict Digested.

Exotic Coating.

Resistant to Bludgeoning. Vulnerable to Slashing.

  • Acidic Touch (2×).
remixed from Gray Ooze by NNimble Co.
Worg
Lvl 1 large hill and field
1028
Savage.

Always crits when attacking a Grappled creature.

Exotic Hide.

Resistant to Slashing. Vulnerable to Piercing.

  • Rip Apart (2×)..

    On hit: Grappled (escape DC 10).

remixed from Worg by NNimble Co.
Lvl 3 flightless bird - Striker
825
Exotic Hide.

Resistant to Slashing. Vulnerable to Piercing.

  • Kick.

    1d4+3. On Crit: Prone. THEN:

  • Peck.

    1d4+3. Vicious.

Lvl 3 crustacean - Controller
436
Exotic Skeleton.

Resistant to Piercing. Vulnerable to Bludgeoning.

Choose one.
  • Big Claw.

    4d4+4 and Grappled (only one at a time).

  • Itty-Bitty Claw (2x).

    1d4+1 and Arterial Bleeding.

Arterial Bleeding: Suffer 1 damage per action spent until healed.

Lvl 3 mushroom - Controller
33
Exotic Coating.

Resistant to Bludgeoning. Vulnerable to Slashing.

Choose one.
  • Mycelial Grip.

    2d6+2 and Grappled.

  • Release Spores.

    (1 use) Enemies in Reach 3 receive 3d6+3 and Dazed. (On Death: if unused, Release Spores for free.)