Frogspawn, Hammer (Anchor), Torch, and to some Octobubbles are all branches of the Euphyllia Coral. As all these species are in the same coral family they may ALL touch freely without consequence. Bubble corals are NOT in that category though.
I have a froggy, two torches and a hammer all tucked together in a "bouquet" that my clowns hosted before I got my BTA