The creatures quickly weave a web which they can propel up to a distance of 5 meters. A DEX saving throw with a difficulty of 10 allows the targeted opponent to avoid the web. Otherwise, the opponent is ensnared in the web: they are paralyzed (no attacks or movement) until they free themselves from the web (STR saving throw with a difficulty of 15).
Evolution
Level 4: Range of 10 meters
Level 8: The saving throw to avoid the web increases to a DEX difficulty of 15.
The saving throw to extricate oneself from the web increases to a STR difficulty of 20