I search how rules works for metaplanes travel.
Core Rulebook p325
Upon your first initiation, you learn how to travel to any of the metaplanes (The Metaplanes, p. 317), if you can use astral projection.
Street Grimoire p140
Only characters who can astrally project can undertake a metaplanar quest unless they gains access to a spirit’s Astral Gateway power (p. 194). Before attempt- ing a quest, the character must prepare herself through a meditation ritual. This simple ritual requires a Force equal to the initiate grade the character wishes to attain. The ritual takes (Force) hours to complete. Successful com- pletion of this ritual means the character can transcend the physical world and face the Dweller on the Threshold (p. 317, SR5). The self-sustaining ritual protects the magician’s body with wards while the character is on the journey.
So, do I need a ritual (and spend Karma on the ritual skill) to go to the metaplanes as written in Street Grimoire, or can i go in as simply as an astral projection (with the exception of the Dweller of the Threshold)?
And about the Dweller, does it have some rules to manage the encouter?