Honestly, I had not fully thought through that. I was drawing inspiration from the tweaks to the starter deck that @EricF suggested
I was only this morning when I was starting to mock up proxy cards and get them as close to originals in shape/style, etc (I’m drafting them in Excel, cuz I’m not tech savvy enough to use something like photoshop)…
When I noticed there were no other ongoing spells in the other starter decks.
Assimilate can gain control of an ongoing spell, but could also target them as upgrades (essentially stealing / removing creep tumor). Other ongoing spells for comparison: Harmony, Two Step, War Drums, Final Showdown, Spirit of the Panda, Dreamscape, Mind Control, Soul Stone, Bird’s Nest, Entangling VInes, & Vortross Emblem.
About half are channeling and half attach. None are “Tech 0”. So it is hard to determine comparable. You could say they attach to the casting hero (or queen) and essentially give them channeling. They essentially work like Upgrades, so their carp type could be changed.
Thematically, having Inject Larva as a spell allows a Queen to cast it, or Zagara, or another hero. Creep tumor could be a building or upgrade alternatively, but being a building makes it much more vulnerable.