Alteration

Metamorphosis. Once per long rest, this horse can change their form for an hour. Roll 1d8 to decide the new form.

Normal Form(Result of 1):

-Nothing and the ability is used.

Nightmare Form(Result of 2): 

-Gains fly speed 90-ft (and hover) and immunity to fire.

-Grant Resistance to Fire damage to a rider while it is on it.

-Sheds Bright Light in a 10-ft radius and Dim Light for an additional 10-ft.

Seahorse Form(Result of 3):

-Gains swim speed 60-ft and Resistance to cold damage.

-Can breathe air & water.

-While underwater,  it can dash without provoking Opportunity Attacks.

Salamander horse Form(Result of 4):

-Gains Vulnerability Cold and immunity to fire.

-At the end of each of its turns, each creature in a 5-ft Emanation originating from the salamander takes 3(1d6) Fire damage.

Scaly horse Form(Result of 5):

-Gains Climb speed 30-ft, and it can climb difficult surfaces, including along ceilings, without needing to make an ability check.

 Horned horse Form(Result of 6):

-Gains a horn and immunity to poisoning, paralysing, charming and poison damage.

-Has Advantage on saving throws against spells and other magical effects.

 Skeleton horse Form(Result of 7):

-Gains immunity to poison damage, exhaustion and poisoning.

-Gains resistance to piercing damage and is vulnerable to bludgeoning damage.

-Does not need to breathe, sleep, eat or drink to survive. 

Worm horse Form(Result of 8): 

-Gains blindness, Tremorsense 40-ft and burrow speed 60-ft.

-Can burrow through solid rock at half its Burrow Speed and leaves a 10-ft diameter tunnel in its wake.

Multiattack (Can not be done in Normal Form). The horse makes two attacks: one with its hooves and one with a special form action.

Hooves (In All Forms). Melee Attack Roll: +6, reach 5 ft. Hit: 9 (2d4 + 4) Bludgeoning damage.If the target is a Large or smaller creature and the horse moved 20+ feet straight toward it immediately before the hit, the target takes an extra 5 (2d4) Bludgeoning damage and has the Prone condition.

Ram (Only In Seahorse Form). Melee Attack Roll: +4, reach 5 ft. Hit: 9 (2d6 + 2) Bludgeoning damage, or 11 (2d8 + 2) Bludgeoning damage if the seahorse moved 20+ feet straight toward the target immediately before the hit.

Bite(Only In Salamander, Scaly & Worm Form ). Melee Attack Roll: +4, reach 5 ft. Hit: 6 (1d8 + 2) piercing damage  (Only In Salamander Form)  plus 3 (1d6) Fire damage.

Radiant Horn(Only In Horned Form). Melee Attack Roll: +7, reach 5 ft. Hit: 9 (1d10 + 4) Radiant damage.

Tail Stinger(Only In Worm Form). Melee Attack Roll: +14, reach 10 ft. Hit: 16 (2d6 + 9) Piercing damage plus 35 (10d6) Poison damage.

Bubble Dash (Only In Seahorse Form). While underwater, the seahorse moves up to half its Swim Speed without provoking Opportunity Attacks.