Sources
CR
Type
Size
Alignment
Movement

Killer Whale

Huge Beast, Unaligned

Armor Class 12 (natural armor)
Hit Points 90 (12d12 + 12)
Speed swim 60 ft.
STR
19
+4
DEX
10
+0
CON
13
+1
INT
3
-4
WIS
12
+1
CHA
7
-2
Skills Perception +3
Senses blindsight 120 ft., passive Perception 13
Languages
Challenge 3 (700 XP)

Traits

Echolocation. The whale can't use its blindsight while deafened.

Hold Breath. The whale can hold its breath for 30 minutes.

Keen Hearing. The whale has advantage on Wisdom (Perception) checks that rely on hearing.

Actions

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit:21 (5d6 + 4) piercing damage.