Gar doesn’t have a letter equivalent, although it could be the letter g (even though Gebo already occupies that role)
There is no rune poem for Gar
The word Gar translates as spear. Raven Kaldera sees it as the spear of the All-Father, his mark upon the runes, claiming his action which brought the runes into this world. The spear is also an epithet of Yggdrasil is also indicated by Mr. Kaldera.
As Yggdrasil, it is a rune of possibility and connection, a doorway that leads to all places. There is also a value of it as the replacement of the “blank rune” used in some practices. It isn’t blank, but rather represents the cosmic “sit tight and hold on” value that things are happening around you, and you need to be in the moment. I sense of similar meaning, but it has more to do with being in that moment, and as all things now are a clear slate for you, the actions you take can lead to anywhere, instead of responding and interacting with things that you have already done. As Yggdrasil is the axis of creation, it has infinite potential and possibility, growing into all worlds, rooted in all worlds. Yggdrasil itself however it is not changed in it’s nature from the worlds, but rather holds stead and balanced, even though imbalance can rage around it. From that center, take action, and shape the maelstrom around you.