Hey there, thanks for asking! Surprisingly... Not yet! I have some slashes in my other effects packs: Super Pixel Effects Pack 1, Super Pixel Effects Pack 2, and Super Pixel Fantasy FX Pack 2.
I'll add swords and slash effects to my idea list for the Gigapack, so you can expect to see some arrive here in the future!
Great question! For this pack, the only difference is that you'd download the asset pack from Patreon instead of from itch. For patrons, I give out itch keys manually for this pack on request since it works a little differently than other packs on itch's end. For almost all other packs, connecting your itch and Patreon accounts lets you download and claim the pack on itch. Becoming a patron also means you'll get access to new packs when I publish them. If you pledge on Patreon and then cancel later, you still get to use all the asset packs you've downloaded- You own them.
In the end, it's just two different ways to support and get the art, and it's your choice! Some folks like to support on Patreon and stay in the loop and help me make more art, while others prefer a one-time purchase or prefer not to set up an additional account. Let me know if you have any other questions about it!
You can still re-download any packs which you've claimed on itch. For this pack, I would have to give you a key manually and then you would be able to get future updates, yes. For most other packs, it's more automatic- You connect your itch/Patreon accounts, find a pack you like here, click the patron-only link, and it should be added to your itch account. This pack works differently on itch's end because of the way it's set up as a free/paid hybrid. On Patreon, I believe once you stop being a member then you would lose access to the downloads from Patreon, unless you had specifically purchased the pack there, which is also possible.
