Triple v's Spikey
Spikey is a useful addition to your toolset. It can be used to create
Triangles, as an alternative to 'Triple', which diagonally splits your Quads.
Generally speaking it's best to stick to Quads and avoid Triangles if
possible. Triangles tend to create smoothing problems in a Sub Division
Surface, though you can sometimes get away with a few well placed Tris.
You can also opt to to work with Triangles as the default Polygon, in the
General Options panel. This is useful if working on low-poly-models for games.
Construct > Sub Divide > Triple (T Key)
Multiply > Extend > Spikey

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