I had a group of Bullywugs ambush the party when they were fighting a giant frog in a clearing in a swamp. The bullywugs were hidden in reeds and sedges around the clearing and they had all readied an action to attack from hiding when their leader called out the order. When they attacked, I allowed them to use both parts of their multiattack (throwing spears from the obscuring vegetation and then leaping into the clearing to follow up with a bite attack).

One of my players cried foul, because a PC using extra attack cannot use the extra attack as part of a reation. I countered that there is nowhere in the rules that equates Multiattack with Extra Attack, so that rule does not apply.

Please say how you would rule this and why.

I had a group of Bullywugs ambush the party when they were fighting a giant frog in a clearing in a swamp. The bullywugs were hidden in reeds and sedges around the clearing and they had all readied an action to attack from hiding when their leader called out the order. When they attacked, I allowed them to use both parts of their multiattack (throwing spears from the obscuring vegetation and then leaping into the clearing to follow up with a bite attack).

One of my players cried foul, because a PC using extra attack cannot use the extra attack as part of a reaction. I countered that there is nowhere in the rules that equates Multiattack with Extra Attack, so that rule does not apply.

Please say how you would rule this and why.

I had a group of Bullywugs ambush the party when they were fighting a giant frog in a clearing in a swamp. The bullywugs were hidden in reeds and sedges around the clearing and they had all readied an action to attack from hiding when their leader called out the order. When they attacked, I allowed them to use both parts of their multiattack (throwing spears from the obscring vegetation and then leaping into the clearing to follow up with a bite attack).

One of my players cried foul, because a PC using extra attack cannot use the extra attack as part of a reation. I countered that there is nowhere in the rules that equates Multiattack with Extra Attack, so that rule does not apply.

Please say how you would rule this and why.

I had a group of Bullywugs ambush the party when they were fighting a giant frog in a clearing in a swamp. The bullywugs were hidden in reeds and sedges around the clearing and they had all readied an action to attack from hiding when their leader called out the order. When they attacked, I allowed them to use both parts of their multiattack (throwing spears from the obscuring vegetation and then leaping into the clearing to follow up with a bite attack).

One of my players cried foul, because a PC using extra attack cannot use the extra attack as part of a reation. I countered that there is nowhere in the rules that equates Multiattack with Extra Attack, so that rule does not apply.

Please say how you would rule this and why.