Here are 15 Testnet Rollups on @Calderaxyz 
All are Free of Cost - Zero cost interaction.
Thank me later.

1) B3 Testnet powered by Caldera
Bridge : b3-testnet.bridge.caldera.xyz

2) Manta Sepolia powered by Caldera
Bridge : manta-sepolia.bridge.caldera.xyz

3) zkXPLA Testnet powered by Caldera
Bridge : xpla-testnet-bridge.vercel.app/bridge

4) TOY CHAIN Testnet by Caldera
Bridge : toy-chain-testnet.bridge.caldera.xyz

5) ZaynZK Testnet powered by Caldera
Bridge : zaynzk-testnet-bridge.vercel.app/bridge

6) Zayn OP Testnet powered by Caldera
Bridge : zayn-op-testnet.bridge.caldera.xyz

7) Ozean Testnet powered by Caldera
Bridge : ozean-testnet.bridge.caldera.xyz

8) rayls-test-chain powered by Caldera
Bridge : rayls-test-chain.bridge.caldera.xyz

9) HappyChain Sepolia powered by Caldera
Bridge : …n-sepolia-redeploy.bridge.caldera.xyz

10) SxT Testnet powered by Caldera
Bridge : sxt-avail-bridge.vercel.app/bridge

11) Mawari Testnet on Caldera
Bridge : …ri-network-testnet.bridge.caldera.xyz