Feat: Great Stature. The user gains +10 hit points and +5 maximum move speed. Magic Transmuter Shield. The Shield Sentinel has a magical barrier that automatically absorbs the first 20 points of spell damage within 120 feet, even if the spell is cast on the Sword Sentinel or Lich Saval. After absorbing 20 points of spell damage, the Shield Sentinel begins charging for 1d4 turns during which time it is dormant and can take no actions. During this time, the Sword Sentinel will fall back to protect the Shield Sentinel to the best of its ability. After this brief charge, the Shield Sentinel will let out a burst of energy that nullifies all spellcasting and magical items/effects for the same number of turns it charged. At the end of this nullification, the Magic Transmuter Shield is restored and reset to zero points. Feat: Shield Master.
Multiattack. The Shield Sentinel makes two standards attacks, one with Shield Bash and the other with Shield Slam or instead uses its turn to activate Castigate or Admonish. Shield Bash. Melee Weapon Attack. +10 to hit, range 5 ft., one target. Hit: 1d8+6 bludgeoning damage. If the target is struck by this attack, it must succeed on a DC 18 Strength (Athletics) check or be knocked prone. Shield Slam. Melee Weapon Attack. +10 to hit, range 5 ft., one target. Hit: 1d8+6 bludgeoning damage. If the target is prone, this attack is made with advantage. Castigate. As an action the Shield Sentinel hunkers down, reducing the next incoming melee damage to 1 and returning double the original damage to the attacker. If the next incoming attack is ranged, the Shield Sentinel reduces the incoming damage to 1 and returns to its normal state. Admonish. (Can only be used when the Shield Sentinel has a portion of its Magic Transmuter Shield available) As an action the Shield Sentinel focuses its Magic Transmuter Shield into a powerful anti-magic beam. This beam can only be fired at a target Concentrating on a spell. The target must make three Concentration checks at disadvantage. Salvation. As a bonus action, the Shield Sentinel swaps places with the Sword Sentinel as long as they are adjacent to one another. This switch provokes no attacks of opportunity. Any remaining movement speed is given to the Sword Sentinel, which may move immediately.