giant spider in the Dungeons and Dragons game DND

Giant Sand Spider

   Size: Large
   Type: Beast
   Armor Class: 14 (natural armor)
   Hit Points: 52 (7d10 + 14)
   Speed: 30 ft, climb 30 ft
   STR: 14 (+2)
   DEX: 16 (+3)
   CON: 14 (+2)
   INT: 2 (-4)
   WIS: 11 (+0)
   CHA: 7 (-2)
   Skills: Athletics +4, Stealth +7
   Senses: Blindsight 10 ft, darkvision 60 ft, passive Perception 10
   Languages: —
   Challenge: 3 (700 XP)

Traits

   Spider Climb: The spider can climb difficult surfaces, including upside-down ceilings, without needing to make an ability check
   Senses Tremors: While in contact with the ground, the spider can sense and pinpoint the location of any creature within 30 feet of it

Actions

   Bite: Melee Weapon Attack: +5 to hit, reach 5 ft, one creature. Hit: 7 (1d8 + 3) piercing damage, and the target must make a DC 11 Constitution saving throw, taking 7 (2d6) poison damage on a failed save. On a save of 5 or more below the DC, the target is also poisoned for 1 minute. The poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on a success.  

  Web: Ranged Weapon Attack: +5 to hit, range 30/60 ft, one creature Large or smaller. Hit: The target is restrained. A creature restrained by the web can use its action to make a DC 12 Strength check, freeing itself on a success. The web is also flammable

Arena Considerations

   Terrain: You could have the arena include sand dunes or structures where the spider can hide and ambush its prey
   Web Traps: You could depict webs scattered across the arena as difficult terrain or even as traps that require Dexterity checks to avoid being restrained
   Behavior: In an arena setting, the spider could be territorial and aggressive, attacking anything that enters its domain. It could also be a creature trained for “spectacle,” exhibiting more predictable but equally dangerous behavior
   Variants: You could consider a larger, more resilient spider for a greater challenge, or even one with more potent poisonous abilities