Let's hear it!
Mine? Teleseed. Mobility, damage, and a high skill ceiling. Sign me up!
TumbleSeed is a deceptively deep roguelike about balancing a seed up a dangerous and ever-changing mountain. · By
Loving the Shield since I can take a few hits. And once I found a wild Pistol seed spawned that thing easily killed three enemies on screen
This isn't a favorite, but: if I see that a seed can damage me, I pretty much avoid it every time. Once I laid down a homing seed without getting out of the way immediately, and it immediately spawned a missile and killed me, so now I kinda grumble "ugh never again" and go with a seed that can't hurt me.
It's hard to pick a fav, but I think it would be the Vertical Laser seed.
It splits the area with an "invisible wall" into two sections with the plot acting as a bridge between them. Not always the most useful, but it's fun and it costs nothing so if things don't work out (and you don't hit yourself in the face) no biggie.