Very cool roleplay! If we had some mechanic, maybe through a zooid, which would buff neighboring zooids stats if Sipho has no movers, this kind of play could work. Or a zooid that is like Grabber or Leech, but doesn't let go of objects and doesn't require lots of energy to maintain hold.
I have a suggestion...
Building off of your idea of a "Grabber/Leech that attaches to objects": The Holdfast zooid.
Type: Utility
Max Health: 10 when un-anchored, 15 when anchored
Range: 3 (similar to Leech zooids)
Nutrition Capacity: 4
Energy Regen/Second: 3 when un-anchored, 10 when anchored
Mass: 2
Drag: 10
Ability: Anchor (Energy Cost: 30, Cooldown: 1) - Attaches itself to a nearby object. Doing so greatly increases the energy regeneration and health of the zooid.
Base zooid cost: 4 Nutrients
Great for making sessile creatures, this zooid is able to sprout "roots" to attach itself to any object (yes, even eggs and spike balls, though the latter is risky). Since sacrificing movement is quite a large trade-off, this zooid offers exceptional energy regeneration compared to other utility zooids when anchored, while also making sure it is not easy to destroy. Also, rather than requiring a constant energy cost for the zooid to hold, a better alternative would be to make it be a toggle ability, ie. spend 30 energy to anchor, and another 30 if you wish to un-anchor.
Good idea!
I wonder how it would work with Zooids from other Siphos around - it might be too powerful as a holder. Although we could always say other Zooids are more "slippery" than stationary rocks. Also state as a toggle might get weird, but if we do it as we do with Flail - global for whole Sipho, it should be okay. I will write this down and propose it as a prototype for next potential Zooid drop.
Thanks for considering my idea! You also nailed the method which it will toggle (which I forgot to mention), i.e. global for whole Sipho like flail.
And yeah...it was designed to be a little bit on the overpowered side, but in my mind, it was to balance out the fact that it only becomes powerful when active and anchored. After all, it's fragile dead weight when it isn't anchored! Nevertheless, I'll leave the balance to you guys, since you will be the ones to playtest the prototype if it does come to fruition. I'm just glad that my suggestion helped!